U.S. patent application number 14/941384 was filed with the patent office on 2016-05-19 for poly(beta-amino alcohols), their preparation, and uses thereof.
This patent application is currently assigned to Massachusetts Institute of Technology. The applicant listed for this patent is Massachusetts Institute of Technology. Invention is credited to Daniel Griffith Anderson, Robert S. Langer, Wendy F. Liu, Minglin Ma.
Application Number | 20160137785 14/941384 |
Document ID | / |
Family ID | 45724089 |
Filed Date | 2016-05-19 |
United States Patent
Application |
20160137785 |
Kind Code |
A1 |
Ma; Minglin ; et
al. |
May 19, 2016 |
POLY(BETA-AMINO ALCOHOLS), THEIR PREPARATION, AND USES THEREOF
Abstract
A new class of poly(beta-amino alcohols) (PBAAs) has been
prepared using combinatorial polymerization. The inventive PBAAs
may be used in biotechnology and biomedical applications as
coatings (such as coatings of films or multilayer films for medical
devices or implants), additives, materials, excipients,
non-biofouling agents, micropatterning agents, and cellular
encapsulation agents. When used as surface coatings, these PBAAs
elicited different levels of inflammation, both in vitro and in
vivo, depending on their chemical structures. The large chemical
diversity of this class of materials allowed us to identify polymer
coatings that inhibit macrophage activation in vitro. Furthermore,
these coatings reduce the recruitment of inflammatory cells, and
reduce fibrosis, following the subcutaneous implantation of
carboxylated polystyrene microparticles. These polymers may be used
to form polyelectrolyte complex capsules for cell encapsulation.
The invention may also have many other biological applications such
as antimicrobial coatings, DNA or siRNA delivery, and stem cell
tissue engineering.
Inventors: |
Ma; Minglin; (Cambridge,
MA) ; Liu; Wendy F.; (Irvine, CA) ; Langer;
Robert S.; (Newton, MA) ; Anderson; Daniel
Griffith; (Framingham, MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Massachusetts Institute of Technology |
Cambridge |
MA |
US |
|
|
Assignee: |
Massachusetts Institute of
Technology
Cambridge
MA
|
Family ID: |
45724089 |
Appl. No.: |
14/941384 |
Filed: |
November 13, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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13819280 |
May 14, 2013 |
9193827 |
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PCT/US2011/049360 |
Aug 26, 2011 |
|
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14941384 |
|
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61377348 |
Aug 26, 2010 |
|
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Current U.S.
Class: |
424/450 ;
424/400; 514/772.7; 525/54.3; 528/407 |
Current CPC
Class: |
C09D 179/02 20130101;
A61K 31/7088 20130101; C08G 73/0206 20130101; Y10T 428/31725
20150401; C08G 59/22 20130101; C08G 73/02 20130101; A61K 9/1273
20130101; A61K 47/59 20170801; A61L 31/10 20130101; A61K 47/34
20130101; C08G 59/306 20130101; C08G 59/50 20130101; C09D 5/1637
20130101 |
International
Class: |
C08G 73/02 20060101
C08G073/02; A61K 47/48 20060101 A61K047/48; A61L 31/10 20060101
A61L031/10; A61K 31/7088 20060101 A61K031/7088; A61K 47/34 20060101
A61K047/34; A61K 9/127 20060101 A61K009/127 |
Claims
1. A polymer of formula: ##STR00070## wherein: each A and B is,
independently, a bond; a substituted or unsubstituted, branched or
unbranched, cyclic or acyclic C.sub.1-20 aliphatic; a substituted
or unsubstituted, branched or unbranched, cyclic or acyclic
C.sub.1-20 heteroaliphatic; substituted or unsubstituted aryl; or a
substituted or unsubstituted heteroaryl; each R.sup.1 and R.sup.2
is, independently, unsubstituted, branched or unbranched, cyclic or
acyclic C.sub.1-20 aliphatic; substituted or unsubstituted aryl; or
a substituted or unsubstituted heteroaryl; each ##STR00071## may
optionally form a cyclic structure by the joining of R.sup.1 and
R.sup.2; each R.sup.3, R.sup.4, and R.sup.5 is hydrogen; a
substituted or unsubstituted, branched or unbranched, cyclic or
acyclic C.sub.1-20 aliphatic; a substituted or unsubstituted,
branched or unbranched, cyclic or acyclic C.sub.1-20
heteroaliphatic; a substituted or unsubstituted aryl; or a
substituted or unsubstituted heteroaryl; each ##STR00072## may
optionally form a cyclic structure; each E and G is, independently,
hydrogen; a substituted or unsubstituted, branched or unbranched,
cyclic or acyclic C.sub.1-20 aliphatic; a substituted or
unsubstituted, branched or unbranched, cyclic or acyclic C.sub.1-20
heteroaliphatic; substituted or unsubstituted aryl; a substituted
or unsubstituted heteroaryl; ##STR00073## n is an integer from 2 to
10,000, inclusive; or a salt thereof.
2. The polymer of claim 1, wherein A is substituted or
unsubstituted, branched or unbranched, cyclic or acyclic C.sub.1-20
aliphatic, or substituted or unsubstituted, branched or unbranched,
cyclic or acyclic C.sub.1-20 heteroaliphatic.
3. The polymer of claim 1, wherein A is substituted or
unsubstituted, branched or unbranched, cyclic or acyclic C.sub.1-20
alkylene.
4. The polymer of claim 1, wherein A is selected from the group
consisting of: ##STR00074## ##STR00075## ##STR00076## wherein: each
R.sup.10 is, independently, hydrogen; a substituted or
unsubstituted, branched or unbranched, cyclic or acyclic C.sub.1-20
aliphatic; a substituted or unsubstituted, branched or unbranched,
cyclic or acyclic C.sub.1-20 heteroaliphatic; substituted or
unsubstituted aryl; a substituted or unsubstituted heteroaryl; or
an N-protecting group; and each q is, independently, an integer
between 0 and 10, inclusive.
5. The polymer of claim 1, wherein ##STR00077## is selected from
the group consisting of: ##STR00078##
6. The polymer of claim 1, wherein B is substituted or
unsubstituted, branched or unbranched, cyclic or acyclic C.sub.1-20
aliphatic, or substituted or unsubstituted, branched or unbranched,
cyclic or acyclic C.sub.1-20 heteroaliphatic.
7. The polymer of claim 1, wherein B is substituted or
unsubstituted, branched or unbranched, cyclic or acyclic C.sub.1-20
alkylene.
8. The polymer of claim 1, wherein B is selected from the group
consisting of: a bond, ##STR00079## ##STR00080## wherein each q is,
independently, an integer between 0 and 10, inclusive.
9. The polymer of claim 1, wherein each R.sup.1 and R.sup.2 is
independently unsubstituted, branched or unbranched, cyclic or
acyclic C.sub.1-20 aliphatic.
10. The polymer of claim 1, wherein each R.sup.1 and R.sup.2 is
independently a substituted or unsubstituted aryl or substituted or
unsubstituted heteroaryl.
11. The polymer of claim 1, wherein R.sup.1 and R.sup.2 are all
unsubstituted C.sub.1-C.sub.6 alkyl.
12. The polymer of claim 1, wherein each R.sup.1 and R.sup.2 is
independently selected from the group consisting of:
##STR00081##
13. The polymer of claim 1, wherein all R.sup.3, R.sup.4, and
R.sup.5 are hydrogen.
14. The polymer of claim 1, wherein each R.sup.3, R.sup.4, and
R.sup.5 is independently selected from the group consisting of:
##STR00082## ##STR00083## ##STR00084##
15. The polymer of claim 1, wherein the weight-average molecular
weight as determined by gel permeation chromatography ranges
between 1,000 and 100,000 Daltons.
16. A polymer prepared by reacting: an epoxide selected from the
group consisting of: ##STR00085## ##STR00086## wherein each q is,
independently, an integer between 0 and 10, inclusive; and an amine
selected from the group consisting of: ##STR00087## ##STR00088##
##STR00089## ##STR00090## ##STR00091##
17. The polymer of claim 16, selected from the group consisting of:
F18, C01, F28, E19, B20, D19, A03, A01, F12, A28, B19, A19, B01,
A20, F19, F10, F20, B12, A10, and A12.
18. A pharmaceutical composition comprising a polymer of claim 1;
and a pharmaceutical agent.
19. A liposome, microparticle, or micelle, each of which comprises
a polymer of claim 1; and an agent to be delivered.
20. A medical device or implant, each of which is coated with a
polymer of claim 1.
21. A surface coated with a polymer of claim 1.
22. A complex comprising a polymer of claim 1; and a
polynucleotide.
23. A method of administering an agent, the method comprising the
step of administering to a subject in need thereof a
therapeutically effective amount of a pharmaceutical composition
comprising: a polymer of claim 1 and an agent to be delivered.
Description
RELATED APPLICATIONS
[0001] The present application is a continuation of and claims
priority under 35 U.S.C. .sctn.120 to U.S. Application, U.S. Ser.
No. 13/819,280, filed May 14, 2013, which is a national stage
filing under 35 U.S.C. .sctn.371 of international PCT application,
PCT/US2011/049360, filed Aug. 26, 2011, which claims priority under
35 U.S.C. .sctn.119(e) to U.S. provisional application, U.S. Ser.
No. 61/377,348, filed Aug. 26, 2010, each of which is incorporated
herein by reference.
BACKGROUND OF THE INVENTION
[0002] In many biomedical applications such as cell encapsulation
and implantations (R. Langer, Adv. Mater. 2009, 21, 3235,) the
biological response of the body to the implanted medical device and
biomaterial play a critical role in determining the long term
success of the implant (J. M. Anderson, Annu. Rev. Mater. Res.
2001, 31, 81; M. T. Novak, J. D. Bryers, W. M. Reichert,
Biomaterials 2009, 30, 1989; D. F. Williams, Biomaterials 2008, 29,
2941.) Often, the acute and chronic inflammatory response caused by
foreign material and the formation of fibrotic tissue around the
device lead to compromised function, device failure, or medical
complications. The so-called foreign body response consists of a
series of complex reactions involving various types of cells,
chemokines, and cytokines. In the simplest view, the recruitment of
inflammatory cells such as neutrophils and macrophages to the
implantation site is characteristic of the early response, i.e.,
acute inflammation, while fibrosis is typically considered the end
result of chronic inflammation. Both the physical and chemical
properties of the biomaterial influence the intensity and/or
duration of the foreign body response. Significant research efforts
have thus been devoted to controlling the foreign body response by
tuning material properties and surface chemistries (B. D. Ratner,
S. J. Bryant, Annu. Rev. Biomed. Eng. 2004, 6, 41; W. K. Ward, J.
Diabetes Sci. Technol. 2008, 2, 768; Y. Onuki, U. Bhardwaj, F.
Papadimitrakopoulos, D. J. Burgess, J. Diabetes Sci. Technol. 2008,
2, 1003.)
[0003] Cationic polymers are an important class of polymers that
have been used extensively in biomedical applications. For example,
in cell encapsulation applications, a polycation is often used as a
component to form a semi-permeable polyelectrolyte complex capsule,
which protects the encapsulated cells from the attack of host
immune systems but allows the facile diffusion of nutrients (T. M.
S. Chang, Nature Reviews Drug Discovery 2005, 4, 221.)
Poly(L-lysine) (PLL) was the first polycation used in
alginate-based islet encapsulation system. It has since been widely
used, but recently it was shown to have biocompatibility issues (G.
Orive et al., Nature Medicine 2003, 9, 104.) Discovery of
alternative, more biocompatible polycations therefore represents a
critical step towards the final clinical success for cell
encapsulation. Another example where polycations are used is in
layer-by-layer (LBL) coatings, which has become one of the most
versatile and robust surface modification approaches for various
biomedical applications (T. Boudou, T. Crouzier, K. Ren, G. Blin,
C. Picart, Adv. Mater. 2010, 22, 441.) The LBL coating involves
alternating adsorption of complementary materials from solution,
for example, positively and negatively charged species or polymers
with hydrogen bond donor and acceptor groups (G. Decher, Science
1997, 277, 1232.) The diversity of cationic polymers used in LBL
coatings have been relatively limited, with poly(allylamine
hydrochloride) (PAH) being commonly used. Thus, development of new
polycations, in particular, those with improved
immuno-compatibility, will have a tremendous impact in biomedical
applications.
SUMMARY OF THE INVENTION
[0004] The present invention originates from the discovery that
poly(beta-amino alcohols) (PBAAs) for biomedical applications may
be prepared by reacting an amine with a diepoxide as shown in the
schemes below.
##STR00001##
[0005] The present invention provides such novel poly(beta-amino
alcohols). The inventive poly(beta-amino alcohols) may be used in
biotechnology and biomedical applications as coatings (such as
coatings of films or multilayer films for medical devices or
implants), additives, materials, excipients, non-biofouling agents,
micropatterning agents, and cellular encapsulation agents. The
inventive polymers may be used for other purposes as well such as,
for example, the administration and/or delivery of therapeutic
agents (e.g., polynucleotide, small molecule, antigen, drug,
protein, peptide, etc.) to a subject, patient, tissue, organ, or
cell. Poly(beta-amino alcohols) of the present invention are
amenable to combinatorial synthesis to generate libraries of
polymers and high-throughput screening to identify polymers with a
desired property.
[0006] In one aspect, the present invention provides novel
poly(beta-amino alcohols) of the formula:
##STR00002##
wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, A, B, n, E,
and G are as defined herein. In another aspect, the present
invention provides novel poly(beta-amino alcohols) of the
formula:
##STR00003##
wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, A, B, n, E,
and G are as defined herein. These poly(beta-amino alcohols) may be
prepared by reacting an amine with a diepoxide. In certain
embodiments, the diepoxide is stereochemically pure (e.g.,
enantiomerically pure). In certain embodiments, the amine is
stereochemically pure (e.g., enantiomerically pure).
[0007] In another aspect, the present invention provides
pharmaceutical compositions comprising a poly(beta-amino alcohol)
of the invention; a pharmaceutical agent; and optionally, a
pharmaceutically acceptable excipient. The pharmaceutical agent of
the composition may be, for example, a polynucleotide, protein,
peptide, or small molecule.
[0008] The invention also provides methods of preparing the
inventive poly(beta-amino alcohols). One or more equivalents of an
amine are allowed to react with one or more equivalents of a
diepoxide under suitable conditions to form a poly(beta-amino
alcohol). Typically, the amines chosen contain between two and five
amine moieties and the diepoxides may include one or more tails of
varying chain lengths and optionally feature various functional
groups and varying degrees of saturation. In certain embodiments,
all the amino groups of the amine are fully reacted with the
epoxide-terminated compound to form tertiary amines. In other
embodiments, all the amino groups of the amine are not fully
reacted with the epoxide-terminated compound to form tertiary
amines thereby resulting in primary or secondary amines in the
poly(beta-amino alcohol). These primary or secondary amines are
left as is or may be reacted with another electrophile. As will be
appreciated by one skilled in the art, reacting an amine with less
than an excess of epoxide-terminated compound will result in a
plurality of different poly(beta-amino alcohols). In certain
embodiments, all the amino groups are not fully functionalized. In
certain embodiments, a single amine and/or a single diepoxide are
used. In other embodiments, two or more different amines and/or two
or more different diepoxides are used. The synthesis of the
poly(beta-amino alcohol) is performed with or without solvent, and
the synthesis may be performed at higher temperatures ranging from
30.degree. C.-100.degree. C., preferably at approximately
50.degree. C.-90.degree. C. The prepared poly(beta-amino alcohols)
may be optionally purified. For example, the mixture of
poly(beta-amino alcohols) may be purified to yield a particular
stereo- or regioisomer. The poly(beta-amino alcohols) may also be
alkylated using an alkyl halide (e.g., methyl iodide) or other
alkylating agent, and/or they may be acylated, or reacted with
other electrophiles.
[0009] Poly(beta-amino alcohols) are also amenable to combinatorial
synthesis to generate libraries of polymers.
[0010] In certain embodiments, the present invention provides
methods of preparing a poly(beta-amino alcohol) of the invention
comprising the step of reacting an amine of the formula:
##STR00004##
with a diepoxide of the formula:
##STR00005##
to form a polymer of the formula:
##STR00006##
wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, A, B, n, E,
and G are as defined herein.
[0011] In another embodiment, the present invention provides
methods of preparing a poly(beta-amino alcohol) of the invention
comprising the step of reacting an amine of the formula:
##STR00007##
with a diepoxide of the formula:
##STR00008##
to form a polymer of formula:
##STR00009##
wherein R.sup.2, R.sup.3, R.sup.4, R.sup.5, B, n, E, and G are as
defined herein.
[0012] The inventive poly(beta-amino alcohols) have many different
and varied applications. They may be used in biotechnology and
biomedical applications as coatings (such as coatings of films or
multilayer films for medical devices or implants), additives,
materials, excipients, non-biofouling agents, micropatterning
agents, and cellular encapsulation agents. The inventive polymers
may be used for other purposes as well such as, for example, the
administration and/or delivery of therapeutic agents (e.g.,
polynucleotide, small molecule, antigen, drug, protein, peptide,
etc.) to a subject, patient, tissue, organ, or cell. The inventive
poly(beta-amino alcohols) are particularly useful in delivering
negatively charged agents (e.g., polynucleotides) given the
tertiary amines available for protonation thus forming a cationic
moiety. For example, the poly(beta-amino alcohol) may be used to
delivery DNA, RNA, or other polynucleotides to a subject or to a
cell.
[0013] In another respect, the invention also provides libraries of
poly(beta-amino alcohols) prepared by the inventive methods. These
poly(beta-amino alcohols) may be prepared and/or screened using
high-throughput techniques involving liquid handlers, robots,
microtiter plates, computers, etc. In certain embodiments, the
poly(beta-amino alcohols) are screened for their ability to
transfect polynucleotides or other agents (e.g., proteins,
peptides, small molecules) into a cell. In certain embodiments, the
poly(beta-amino alcohols) are screened for their
biocompatibility.
DEFINITIONS
[0014] Definitions of specific functional groups and chemical terms
are described in more detail below. For purposes of this invention,
the chemical elements are identified in accordance with the
Periodic Table of the Elements, CAS version, Handbook of Chemistry
and Physics, 75.sup.th Ed., inside cover, and specific functional
groups are generally defined as described therein. Additionally,
general principles of organic chemistry, as well as specific
functional moieties and reactivity, are described in Organic
Chemistry, Thomas Sorrell, University Science Books, Sausalito:
1999, the entire contents of which are incorporated herein by
reference.
[0015] Certain compounds of the present invention may exist in
particular geometric or stereoisomeric forms. The present invention
contemplates all such compounds, including cis- and trans-isomers,
R- and S-enantiomers, diastereomers, (D)-isomers, (L)-isomers, the
racemic mixtures thereof, and other mixtures thereof, as falling
within the scope of the invention. Additional asymmetric carbon
atoms may be present in a substituent such as an alkyl group. All
such isomers, as well as mixtures thereof, are intended to be
included in this invention.
[0016] Isomeric mixtures containing any of a variety of isomer
ratios may be utilized in accordance with the present invention.
For example, where only two isomers are combined, mixtures
containing 50:50, 60:40, 70:30, 80:20, 90:10, 95:5, 96:4, 97:3,
98:2, 99:1, or 100:0 isomer ratios are all contemplated by the
present invention. Those of ordinary skill in the art will readily
appreciate that analogous ratios are contemplated for more complex
isomer mixtures.
[0017] If, for instance, a particular enantiomer of a compound of
the present invention is desired, it may be prepared by asymmetric
synthesis, or by derivation with a chiral auxiliary, where the
resulting diastereomeric mixture is separated and the auxiliary
group cleaved to provide the pure desired enantiomers.
Alternatively, where the molecule contains a basic functional
group, such as amino, or an acidic functional group, such as
carboxyl, diastereomeric salts are formed with an appropriate
optically-active acid or base, followed by resolution of the
diastereomers thus formed by fractional crystallization or
chromatographic means well known in the art, and subsequent
recovery of the pure enantiomers.
[0018] The "enantiomeric excess" of a substance is a measure of how
pure a desired enantiomer is relative to the undesired enantiomer.
Enantiomeric excess is defined as the absolute difference between
the mole fraction of each enantiomer which is most often expressed
as a percent enantiomeric excess. For mixtures of diastereomers,
there are analogous definitions and uses for "diastereomeric
excess" and percent diastereomeric excess. For example, a sample
with 70% of R isomer and 30% of S will have an enantiomeric excess
of 40%. This can also be thought of as a mixture of 40% pure R with
60% of a racemic mixture (which contributes 30% R and 30% S to the
overall composition).
[0019] One of ordinary skill in the art will appreciate that the
synthetic methods, as described herein, utilize a variety of
protecting groups. By the term "protecting group," as used herein,
it is meant that a particular functional moiety, e.g., O, S, or N,
is temporarily blocked so that a reaction can be carried out
selectively at another reactive site in a multifunctional compound.
In certain embodiments, a protecting group reacts selectively in
good yield to give a protected substrate that is stable to the
projected reactions; the protecting group should be selectively
removable in good yield by readily available, preferably non-toxic
reagents that do not attack the other functional groups; the
protecting group forms an easily separable derivative (more
preferably without the generation of new stereogenic centers); and
the protecting group has a minimum of additional functionality to
avoid further sites of reaction. As detailed herein, oxygen,
sulfur, nitrogen, and carbon protecting groups may be utilized.
Hydroxyl protecting groups include methyl, methoxylmethyl (MOM),
methylthiomethyl (MTM), t-butylthiomethyl,
(phenyldimethylsilyl)methoxymethyl (SMOM), benzyloxymethyl (BOM),
p-methoxybenzyloxymethyl (PMBM), (4-methoxyphenoxy)methyl (p-AOM),
guaiacolmethyl (GUM), t-butoxymethyl, 4-pentenyloxymethyl (POM),
siloxymethyl, 2-methoxyethoxymethyl (MEM),
2,2,2-trichloroethoxymethyl, bis(2-chloroethoxy)methyl,
2-(trimethylsilyl)ethoxymethyl (SEMOR), tetrahydropyranyl (THP),
3-bromotetrahydropyranyl, tetrahydrothiopyranyl,
1-methoxycyclohexyl, 4-methoxytetrahydropyranyl (MTHP),
4-methoxytetrahydrothiopyranyl, 4-methoxytetrahydrothiopyranyl
S,S-dioxide, 1-[(2-chloro-4-methyl)phenyl]-4-methoxypiperidin-4-yl
(CTMP), 1,4-dioxan-2-yl, tetrahydrofuranyl, tetrahydrothiofuranyl,
2,3,3a,4,5,6,7,7a-octahydro-7,8,8-trimethyl-4,7-methanobenzofuran-2-yl,
1-ethoxyethyl, 1-(2-chloroethoxy)ethyl, 1-methyl-1-methoxyethyl,
1-methyl-1-benzyloxyethyl, 1-methyl-1-benzyloxy-2-fluoroethyl,
2,2,2-trichloroethyl, 2-trimethylsilylethyl,
2-(phenylselenyl)ethyl, t-butyl, allyl, p-chlorophenyl,
p-methoxyphenyl, 2,4-dinitrophenyl, benzyl, p-methoxybenzyl,
3,4-dimethoxybenzyl, o-nitrobenzyl, p-nitrobenzyl, p-halobenzyl,
2,6-dichlorobenzyl, p-cyanobenzyl, p-phenylbenzyl, 2-picolyl,
4-picolyl, 3-methyl-2-picolyl N-oxido, diphenylmethyl,
p,p'-dinitrobenzhydryl, 5-dibenzosuberyl, triphenylmethyl,
.alpha.-naphthyldiphenylmethyl, p-methoxyphenyldiphenylmethyl,
di(p-methoxyphenyl)phenylmethyl, tri(p-methoxyphenyl)methyl,
4-(4'-bromophenacyloxyphenyl)diphenylmethyl,
4,4',4''-tris(4,5-dichlorophthalimidophenyl)methyl,
4,4',4''-tris(levulinoyloxyphenyl)methyl,
4,4',4''-tris(benzoyloxyphenyl)methyl,
3-(imidazol-1-yl)bis(4',4''-dimethoxyphenyl)methyl,
1,1-bis(4-methoxyphenyl)-1'-pyrenylmethyl, 9-anthryl,
9-(9-phenyl)xanthenyl, 9-(9-phenyl-10-oxo)anthryl,
1,3-benzodithiolan-2-yl, benzisothiazolyl S,S-dioxido,
trimethylsilyl (TMS), triethylsilyl (TES), triisopropylsilyl
(TIPS), dimethylisopropylsilyl (IPDMS), diethylisopropylsilyl
(DEIPS), dimethylthexylsilyl, t-butyldimethylsilyl (TBDMS),
t-butyldiphenylsilyl (TBDPS), tribenzylsilyl, tri-p-xylylsilyl,
triphenylsilyl, diphenylmethylsilyl (DPMS),
t-butylmethoxyphenylsilyl (TBMPS), formate, benzoylformate,
acetate, chloroacetate, dichloroacetate, trichloroacetate,
trifluoroacetate, methoxyacetate, triphenylmethoxyacetate,
phenoxyacetate, p-chlorophenoxyacetate, 3-phenylpropionate,
4-oxopentanoate (levulinate), 4,4-(ethylenedithio)pentanoate
(levulinoyldithioacetal), pivaloate, adamantoate, crotonate,
4-methoxycrotonate, benzoate, p-phenylbenzoate,
2,4,6-trimethylbenzoate (mesitoate), alkyl methyl carbonate,
9-fluorenylmethyl carbonate (Fmoc), alkyl ethyl carbonate, alkyl
2,2,2-trichloroethyl carbonate (Troc), 2-(trimethylsilyl)ethyl
carbonate (TMSEC), 2-(phenylsulfonyl)ethyl carbonate (Psec),
2-(triphenylphosphonio)ethyl carbonate (Peoc), alkyl isobutyl
carbonate, alkyl vinyl carbonate alkyl allyl carbonate, alkyl
p-nitrophenyl carbonate, alkyl benzyl carbonate, alkyl
p-methoxybenzyl carbonate, alkyl 3,4-dimethoxybenzyl carbonate,
alkyl o-nitrobenzyl carbonate, alkyl p-nitrobenzyl carbonate, alkyl
S-benzyl thiocarbonate, 4-ethoxy-1-napththyl carbonate, methyl
dithiocarbonate, 2-iodobenzoate, 4-azidobutyrate,
4-nitro-4-methylpentanoate, o-(dibromomethyl)benzoate,
2-formylbenzenesulfonate, 2-(methylthiomethoxy)ethyl,
4-(methylthiomethoxy)butyrate, 2-(methylthiomethoxymethyl)benzoate,
2,6-dichloro-4-methylphenoxyacetate,
2,6-dichloro-4-(1,1,3,3-tetramethylbutyl)phenoxyacetate, 2,4-bis
(1,1-dimethylpropyl)phenoxyacetate, chlorodiphenylacetate,
isobutyrate, monosuccinoate, (E)-2-methyl-2-butenoate,
o-(methoxycarbonyl)benzoate, .alpha.-naphthoate, nitrate, alkyl
N,N,N',N'-tetramethylphosphorodiamidate, alkyl N-phenylcarbamate,
borate, dimethylphosphinothioyl, alkyl 2,4-dinitrophenylsulfenate,
sulfate, methanesulfonate (mesylate), benzylsulfonate, and tosylate
(Ts). For protecting 1,2- or 1,3-diols, the protecting groups
include methylene acetal, ethylidene acetal, 1-t-butylethylidene
ketal, 1-phenylethylidene ketal, (4-methoxyphenyl)ethylidene
acetal, 2,2,2-trichloroethylidene acetal, acetonide,
cyclopentylidene ketal, cyclohexylidene ketal, cycloheptylidene
ketal, benzylidene acetal, p-methoxybenzylidene acetal,
2,4-dimethoxybenzylidene ketal, 3,4-dimethoxybenzylidene acetal,
2-nitrobenzylidene acetal, methoxymethylene acetal, ethoxymethylene
acetal, dimethoxymethylene ortho ester, 1-methoxyethylidene ortho
ester, 1-ethoxyethylidine ortho ester, 1,2-dimethoxyethylidene
ortho ester, .alpha.-methoxybenzylidene ortho ester,
1-(N,N-dimethylamino)ethylidene derivative,
.alpha.-(N,N'-dimethylamino)benzylidene derivative,
2-oxacyclopentylidene ortho ester, di-t-butylsilylene group (DTBS),
1,3-(1,1,3,3-tetraisopropyldisiloxanylidene) derivative (TIPDS),
tetra-t-butoxydisiloxane-1,3-diylidene derivative (TBDS), cyclic
carbonates, cyclic boronates, ethyl boronate, and phenyl boronate.
Amino-protecting groups include methyl carbamate, ethyl carbamante,
9-fluorenylmethyl carbamate (Fmoc), 9-(2-sulfo)fluorenylmethyl
carbamate, 9-(2,7-dibromo)fluoroenylmethyl carbamate,
2,7-di-t-butyl-[9-(10,10-dioxo-10,10,10,10-tetrahydrothioxanthy]methyl
carbamate (DBD-Tmoc), 4-methoxyphenacyl carbamate (Phenoc),
2,2,2-trichloroethyl carbamate (Troc), 2-trimethylsilylethyl
carbamate (Teoc), 2-phenylethyl carbamate (hZ),
1-(1-adamantyl)-1-methylethyl carbamate (Adpoc),
1,1-dimethyl-2-haloethyl carbamate, 1,1-dimethyl-2,2-dibromoethyl
carbamate (DB-t-BOC), 1,1-dimethyl-2,2,2-trichloroethyl carbamate
(TCBOC), 1-methyl-1-(4-biphenylyl)ethyl carbamate (Bpoc),
1-(3,5-di-t-butylphenyl)-1-methylethyl carbamate (t-Bumeoc), 2-(2'-
and 4'-pyridyl)ethyl carbamate (Pyoc),
2-(N,N-dicyclohexylcarboxamido)ethyl carbamate, t-butyl carbamate
(BOC), 1-adamantyl carbamate (Adoc), vinyl carbamate (Voc), allyl
carbamate (Alloc), 1-isopropylallyl carbamate (Ipaoc), cinnamyl
carbamate (Coc), 4-nitrocinnamyl carbamate (Noc), 8-quinolyl
carbamate, N-hydroxypiperidinyl carbamate, alkyldithio carbamate,
benzyl carbamate (Cbz), p-methoxybenzyl carbamate (Moz),
p-nitobenzyl carbamate, p-bromobenzyl carbamate, p-chlorobenzyl
carbamate, 2,4-dichlorobenzyl carbamate, 4-methylsulfinylbenzyl
carbamate (Msz), 9-anthrylmethyl carbamate, diphenylmethyl
carbamate, 2-methylthioethyl carbamate, 2-methylsulfonylethyl
carbamate, 2-(p-toluenesulfonyl)ethyl carbamate,
[2-(1,3-dithianyl)]methyl carbamate (Dmoc), 4-methylthiophenyl
carbamate (Mtpc), 2,4-dimethylthiophenyl carbamate (Bmpc),
2-phosphonioethyl carbamate (Peoc), 2-triphenylphosphonio isopropyl
carbamate (Ppoc), 1,1-dimethyl-2-cyanoethyl carbamate,
m-chloro-p-acyloxybenzyl carbamate, p-(dihydroxyboryl)benzyl
carbamate, 5-benzisoxazolylmethyl carbamate,
2-(trifluoromethyl)-6-chromonylmethyl carbamate (Tcroc),
m-nitrophenyl carbamate, 3,5-dimethoxybenzyl carbamate,
o-nitrobenzyl carbamate, 3,4-dimethoxy-6-nitrobenzyl carbamate,
phenyl(o-nitrophenyl)methyl carbamate, phenothiazinyl-(10)-carbonyl
derivative, N'-p-toluenesulfonylaminocarbonyl derivative,
N'-phenylaminothiocarbonyl derivative, t-amyl carbamate, S-benzyl
thiocarbamate, p-cyanobenzyl carbamate, cyclobutyl carbamate,
cyclohexyl carbamate, cyclopentyl carbamate, cyclopropylmethyl
carbamate, p-decyloxybenzyl carbamate, 2,2-dimethoxycarbonylvinyl
carbamate, o-(N,N-dimethylcarboxamido)benzyl carbamate,
1,1-dimethyl-3-(N,N-dimethylcarboxamido)propyl carbamate,
1,1-dimethylpropynyl carbamate, di(2-pyridyl)methyl carbamate,
2-furanylmethyl carbamate, 2-iodoethyl carbamate,
isoborynlcarbamate, isobutyl carbamate, isonicotinyl carbamate,
p-(p'-methoxyphenylazo)benzyl carbamate, 1-methylcyclobutyl
carbamate, 1-methylcyclohexyl carbamate,
1-methyl-1-cyclopropylmethyl carbamate,
1-methyl-1-(3,5-dimethoxyphenyl)ethyl carbamate,
1-methyl-1-(p-phenylazophenyl)ethyl carbamate,
1-methyl-1-phenylethyl carbamate, 1-methyl-1-(4-pyridyl)ethyl
carbamate, phenyl carbamate, p-(phenylazo)benzyl carbamate,
2,4,6-tri-t-butylphenyl carbamate, 4-(trimethylammonium)benzyl
carbamate, 2,4,6-trimethylbenzyl carbamate, formamide, acetamide,
chloroacetamide, trichloroacetamide, trifluoroacetamide,
phenylacetamide, 3-phenylpropanamide, picolinamide,
3-pyridylcarboxamide, N-benzoylphenylalanyl derivative, benzamide,
p-phenylbenzamide, o-nitophenylacetamide, o-nitrophenoxyacetamide,
acetoacetamide, (N'-dithiobenzyloxycarbonylamino)acetamide,
3-(p-hydroxyphenyl)propanamide, 3-(o-nitrophenyl)propanamide,
2-methyl-2-(o-nitrophenoxy)propanamide,
2-methyl-2-(o-phenylazophenoxy)propanamide, 4-chlorobutanamide,
3-methyl-3-nitrobutan amide, o-nitrocinnamide, N-acetylmethionine
derivative, o-nitrobenzamide, o-(benzoyloxymethyl)benzamide,
4,5-diphenyl-3-oxazolin-2-one, N-phthalimide, N-dithiasuccinimide
(Dts), N-2,3-diphenylmaleimide, N-2,5-dimethylpyrrole,
N-1,1,4,4-tetramethyldisilylazacyclopentane adduct (STABASE),
5-substituted 1,3-dimethyl-1,3,5-triazacyclohexan-2-one,
5-substituted 1,3-dibenzyl-1,3,5-triazacyclohexan-2-one,
1-substituted 3,5-dinitro-4-pyridone, N-methylamine, N-allylamine,
N-[2-(trimethylsilyl)ethoxy]methyl amine (SEM),
N-3-acetoxypropylamine,
N-(1-isopropyl-4-nitro-2-oxo-3-pyroolin-3-yl)amine, quaternary
ammonium salts, N-benzylamine, N-di(4-methoxyphenyl)methylamine,
N-5-dibenzosuberylamine, N-triphenylmethylamine (Tr),
N-[(4-methoxyphenyl)diphenylmethyl]amine (MMTr),
N-9-phenylfluorenylamine (PhF),
N-2,7-dichloro-9-fluorenylmethyleneamine, N-ferrocenylmethylamino
(Fcm), N-2-picolylamino N'-oxide, N-1,1-dimethylthiomethyleneamine,
N-benzylideneamine, N-p-methoxybenzylideneamine,
N-diphenylmethyleneamine, N-[(2-pyridyl)mesityl]methyleneamine,
N-(N',N'-dimethylaminomethylene)amine, N,N'-isopropylidenediamine,
N-p-nitrobenzylideneamine, N-salicylideneamine,
N-5-chlorosalicylideneamine,
N-(5-chloro-2-hydroxyphenyl)phenylmethyleneamine,
N-cyclohexylideneamine, N-(5,5-dimethyl-3-oxo-1-cyclohexenyl)amine,
N-borane derivative, N-diphenylborinic acid derivative,
N-[phenyl(pentacarbonylchromium- or tungsten)carbonyl]amine,
N-copper chelate, N-zinc chelate, N-nitroamine, N-nitrosoamine,
amine N-oxide, diphenylphosphinamide (Dpp),
dimethylthiophosphinamide (Mpt), diphenylthiophosphinamide (Ppt),
dialkyl phosphoramidates, dibenzyl phosphoramidate, diphenyl
phosphoramidate, benzenesulfenamide, o-nitrobenzenesulfenamide
(Nps), 2,4-dinitrobenzenesulfenamide,
pentachlorobenzenesulfenamide, 2-nitro-4-methoxybenzenesulfenamide,
triphenylmethylsulfenamide, 3-nitropyridinesulfenamide (Npys),
p-toluenesulfonamide (Ts), benzenesulfonamide,
2,3,6,-trimethyl-4-methoxybenzenesulfonamide (Mtr),
2,4,6-trimethoxybenzenesulfonamide (Mtb),
2,6-dimethyl-4-methoxybenzenesulfonamide (Pme),
2,3,5,6-tetramethyl-4-methoxybenzenesulfonamide (Mte),
4-methoxybenzenesulfonamide (Mbs),
2,4,6-trimethylbenzenesulfonamide (Mts),
2,6-dimethoxy-4-methylbenzenesulfonamide (iMds),
2,2,5,7,8-pentamethylchroman-6-sulfonamide (Pmc),
methanesulfonamide (Ms), .beta.-trimethylsilylethanesulfonamide
(SES), 9-anthracenesulfonamide,
4-(4',8'-dimethoxynaphthylmethyl)benzenesulfonamide (DNMBS),
benzylsulfonamide, trifluoromethylsulfonamide, and
phenacylsulfonamide. Exemplary protecting groups are detailed
herein, however, it will be appreciated that the present invention
is not intended to be limited to these protecting groups; rather, a
variety of additional equivalent protecting groups can be readily
identified using the above criteria and utilized in the method of
the present invention. Additionally, a variety of protecting groups
are described in Protective Groups in Organic Synthesis, Third Ed.
Greene, T. W. and Wuts, P. G., Eds., John Wiley & Sons, New
York: 1999, the entire contents of which are hereby incorporated by
reference.
[0020] It will be appreciated that the compounds, as described
herein, may be substituted with any number of substituents or
functional moieties. In general, the term "substituted" whether
preceded by the term "optionally" or not, and substituents
contained in formulas of this invention, refer to the replacement
of hydrogen radicals in a given structure with the radical of a
specified substituent. When more than one position in any given
structure may be substituted with more than one substituent
selected from a specified group, the substituent may be either the
same or different at every position. As used herein, the term
"substituted" is contemplated to include all permissible
substituents of organic compounds. In a broad aspect, the
permissible substituents include acyclic and cyclic, branched and
unbranched, carbocyclic and heterocyclic, aromatic and nonaromatic
substituents of organic compounds. For purposes of this invention,
heteroatoms such as nitrogen may have hydrogen substituents and/or
any permissible substituents of organic compounds described herein
which satisfy the valencies of the heteroatoms. Furthermore, this
invention is not intended to be limited in any manner by the
permissible substituents of organic compounds. Combinations of
substituents and variables envisioned by this invention are
preferably those that result in the formation of stable compounds
useful in the treatment of diseases or disorders. The term
"stable", as used herein, preferably refers to compounds which
possess stability sufficient to allow manufacture and which
maintain the integrity of the compound for a sufficient period of
time to be detected and preferably for a sufficient period of time
to be useful for the purposes detailed herein.
[0021] The term "aliphatic," as used herein, includes both
saturated and unsaturated, straight chain (i.e., unbranched),
branched, acyclic, cyclic, or polycyclic aliphatic hydrocarbons,
which are optionally substituted with one or more functional
groups. As will be appreciated by one of ordinary skill in the art,
"aliphatic" is intended herein to include, but is not limited to,
alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and cycloalkynyl
moieties. Thus, as used herein, the term "alkyl" includes straight,
branched and cyclic alkyl groups. An analogous convention applies
to other generic terms such as "alkenyl," "alkynyl," and the like.
Furthermore, as used herein, the terms "alkyl," "alkenyl,"
"alkynyl," and the like encompass both substituted and
unsubstituted groups. In certain embodiments, as used herein,
"lower alkyl" is used to indicate those alkyl groups (cyclic,
acyclic, substituted, unsubstituted, branched or unbranched) having
1-6 carbon atoms.
[0022] In certain embodiments, the alkyl, alkenyl, and alkynyl
groups employed in the invention contain 1-20 aliphatic carbon
atoms. In certain other embodiments, the alkyl, alkenyl, and
alkynyl groups employed in the invention contain 1-10 aliphatic
carbon atoms. In yet other embodiments, the alkyl, alkenyl, and
alkynyl groups employed in the invention contain 1-8 aliphatic
carbon atoms. In still other embodiments, the alkyl, alkenyl, and
alkynyl groups employed in the invention contain 1-6 aliphatic
carbon atoms. In yet other embodiments, the alkyl, alkenyl, and
alkynyl groups employed in the invention contain 1-4 carbon atoms.
Illustrative aliphatic groups thus include, but are not limited to,
for example, methyl, ethyl, n-propyl, isopropyl, cyclopropyl,
--CH.sub.2-cyclopropyl, vinyl, allyl, n-butyl, sec-butyl, isobutyl,
tert-butyl, cyclobutyl, --CH.sub.2-cyclobutyl, n-pentyl,
sec-pentyl, isopentyl, tert-pentyl, cyclopentyl,
--CH.sub.2-cyclopentyl, n-hexyl, sec-hexyl, cyclohexyl,
--CH.sub.2-cyclohexyl moieties and the like, which again, may bear
one or more substituents. Alkenyl groups include, but are not
limited to, for example, ethenyl, propenyl, butenyl,
1-methyl-2-buten-1-yl, and the like. Representative alkynyl groups
include, but are not limited to, ethynyl, 2-propynyl (propargyl),
1-propynyl, and the like.
[0023] The term "alkyl" as used herein refers to saturated,
straight- or branched-chain hydrocarbon radicals derived from a
hydrocarbon moiety containing between one and twenty carbon atoms
by removal of a single hydrogen atom. Examples of alkyl radicals
include, but are not limited to, methyl, ethyl, propyl, isopropyl,
n-butyl, tert-butyl, n-pentyl, neopentyl, n-hexyl, n-heptyl,
n-octyl, n-decyl, n-undecyl, and dodecyl.
[0024] The term "alkenyl" denotes a monovalent group derived from a
hydrocarbon moiety having at least one carbon-carbon double bond by
the removal of a single hydrogen atom. Alkenyl groups include, for
example, ethenyl, propenyl, butenyl, 1-methyl-2-buten-1-yl, and the
like.
[0025] The term "alkynyl" as used herein refers to a monovalent
group derived form a hydrocarbon having at least one carbon-carbon
triple bond by the removal of a single hydrogen atom.
Representative alkynyl groups include ethynyl, 2-propynyl
(propargyl), 1-propynyl, and the like.
[0026] The term "alkoxy" or "thioalkyl" as used herein refers to an
alkyl group, as previously defined, attached to the parent molecule
through an oxygen atom or through a sulfur atom. In certain
embodiments, the alkyl, alkenyl, and alkynyl groups contain 1-20
alipahtic carbon atoms. In certain other embodiments, the alkyl,
alkenyl, and alkynyl groups contain 1-10 aliphatic carbon atoms. In
yet other embodiments, the alkyl, alkenyl, and alkynyl groups
employed in the invention contain 1-8 aliphatic carbon atoms. In
still other embodiments, the alkyl, alkenyl, and alkynyl groups
contain 1-6 aliphatic carbon atoms. In yet other embodiments, the
alkyl, alkenyl, and alkynyl groups contain 1-4 aliphatic carbon
atoms. Examples of alkoxy, include but are not limited to, methoxy,
ethoxy, propoxy, isopropoxy, n-butoxy, tert-butoxy, neopentoxy, and
n-hexoxy. Examples of thioalkyl include, but are not limited to,
methylthio, ethylthio, propylthio, isopropylthio, n-butylthio, and
the like.
[0027] The term "alkylamino" refers to a group having the structure
--NHR', wherein R' is aliphatic, as defined herein. In certain
embodiments, the aliphatic group contains 1-20 aliphatic carbon
atoms. In certain other embodiments, the aliphatic group contains
1-10 aliphatic carbon atoms. In yet other embodiments, the
aliphatic group employed in the invention contain 1-8 aliphatic
carbon atoms. In still other embodiments, the aliphatic group
contains 1-6 aliphatic carbon atoms. In yet other embodiments, the
aliphatic group contains 1-4 aliphatic carbon atoms. Examples of
alkylamino groups include, but are not limited to, methylamino,
ethylamino, n-propylamino, iso-propylamino, cyclopropylamino,
n-butylamino, tert-butylamino, neopentylamino, n-pentylamino,
hexylamino, cyclohexylamino, and the like.
[0028] The term "carboxylic acid" as used herein refers to a group
of formula --CO.sub.2H.
[0029] The term "dialkylamino" refers to a group having the
structure --NRR', wherein R and R' are each an aliphatic group, as
defined herein. R and R' may be the same or different in an
dialkyamino moiety. In certain embodiments, the aliphatic groups
contains 1-20 aliphatic carbon atoms. In certain other embodiments,
the aliphatic groups contains 1-10 aliphatic carbon atoms. In yet
other embodiments, the aliphatic groups employed in the invention
contain 1-8 aliphatic carbon atoms. In still other embodiments, the
aliphatic groups contains 1-6 aliphatic carbon atoms. In yet other
embodiments, the aliphatic groups contains 1-4 aliphatic carbon
atoms. Examples of dialkylamino groups include, but are not limited
to, dimethylamino, methyl ethylamino, diethylamino,
methylpropylamino, di(n-propyl)amino, di(iso-propyl)amino,
di(cyclopropyl)amino, di(n-butyl)amino, di(tert-butyl)amino,
di(neopentyl)amino, di(n-pentyl)amino, di(hexyl)amino,
di(cyclohexyl)amino, and the like. In certain embodiments, R and R'
are linked to form a cyclic structure. The resulting cyclic
structure may be aromatic or non-aromatic. Examples of cyclic
diaminoalkyl groups include, but are not limited to, aziridinyl,
pyrrolidinyl, piperidinyl, morpholinyl, pyrrolyl, imidazolyl,
1,3,4-trianolyl, and tetrazolyl.
[0030] Some examples of substituents of the above-described
aliphatic (and other) moieties of compounds of the invention
include, but are not limited to aliphatic; heteroaliphatic; aryl;
heteroaryl; arylalkyl; heteroarylalkyl; alkoxy; aryloxy;
heteroalkoxy; heteroaryloxy; alkylthio; arylthio; heteroalkylthio;
heteroarylthio; F; Cl; Br; I; --OH; --NO.sub.2; --CN; --CF.sub.3;
--CH.sub.2CF.sub.3; --CHCl.sub.2; --CH.sub.2OH;
--CH.sub.2CH.sub.2OH; --CH.sub.2NH.sub.2;
--CH.sub.2SO.sub.2CH.sub.3; --C(O)R.sub.x; --OC.sub.2(R.sub.x);
--CON(R.sub.x).sub.2; --OC(O)R.sub.x; --OCO.sub.2R.sub.x;
--OCON(R.sub.x).sub.2; --N(R.sub.x).sub.2; --S(O).sub.2R.sub.x;
--NR.sub.x(CO)R.sub.x wherein each occurrence of R.sub.x
independently includes, but is not limited to, aliphatic,
heteroaliphatic, aryl, heteroaryl, arylalkyl, or heteroarylalkyl,
wherein any of the aliphatic, heteroaliphatic, arylalkyl, or
heteroarylalkyl substituents described above and herein may be
substituted or unsubstituted, branched or unbranched, cyclic or
acyclic, and wherein any of the aryl or heteroaryl substituents
described above and herein may be substituted or unsubstituted.
Additional examples of generally applicable substituents are
illustrated by the specific embodiments shown in the Examples that
are described herein.
[0031] In general, the terms "aryl" and "heteroaryl," as used
herein, refer to stable mono- or polycyclic, heterocyclic,
polycyclic, and polyheterocyclic unsaturated moieties having
preferably 3-14 carbon atoms, each of which may be substituted or
unsubstituted. Substituents include, but are not limited to, any of
the previously mentioned substitutents, i.e., the substituents
recited for aliphatic moieties, or for other moieties as disclosed
herein, resulting in the formation of a stable compound. In certain
embodiments of the present invention, "aryl" refers to a mono- or
bicyclic carbocyclic ring system having one or two aromatic rings
including, but not limited to, phenyl, naphthyl,
tetrahydronaphthyl, indanyl, indenyl, and the like. In certain
embodiments of the present invention, the term "heteroaryl," as
used herein, refers to a cyclic aromatic radical having from five
to ten ring atoms of which one ring atom is selected from S, O, and
N; zero, one, or two ring atoms are additional heteroatoms
independently selected from S, O, and N; and the remaining ring
atoms are carbon, the radical being joined to the rest of the
molecule via any of the ring atoms, such as, for example, pyridyl,
pyrazinyl, pyrimidinyl, pyrrolyl, pyrazolyl, imidazolyl, thiazolyl,
oxazolyl, isooxazolyl, thiadiazolyl, oxadiazolyl, thiophenyl,
furanyl, quinolinyl, isoquinolinyl, and the like.
[0032] It will be appreciated that aryl and heteroaryl groups can
be unsubstituted or substituted, wherein substitution includes
replacement of one, two, three, or more of the hydrogen atoms
thereon independently with any one or more of the following
moieties including, but not limited to: aliphatic; heteroaliphatic;
aryl; heteroaryl; arylalkyl; heteroarylalkyl; alkoxy; aryloxy;
heteroalkoxy; heteroaryloxy; alkylthio; arylthio; heteroalkylthio;
heteroarylthio; --F; --Cl; --Br; --I; --OH; --NO.sub.2; --CN;
--CF.sub.3; --CH.sub.2CF.sub.3; --CHCl.sub.2; --CH.sub.2OH;
--CH.sub.2CH.sub.2OH; --CH.sub.2NH.sub.2;
--CH.sub.2SO.sub.2CH.sub.3; --C(O)R.sub.x; --OC.sub.2(R.sub.x);
--CON(R.sub.x).sub.2; --OC(O)R.sub.x; --OCO.sub.2R.sub.x;
--OCON(R.sub.x).sub.2; --N(R.sub.x).sub.2; --S(O).sub.2R.sub.x;
--NR.sub.x(CO)R.sub.x, wherein each occurrence of R.sub.x
independently includes, but is not limited to, aliphatic,
heteroaliphatic, aryl, heteroaryl, arylalkyl, or heteroarylalkyl,
wherein any of the aliphatic, heteroaliphatic, arylalkyl, or
heteroarylalkyl substituents described above and herein may be
substituted or unsubstituted, branched or unbranched, cyclic or
acyclic, and wherein any of the aryl or heteroaryl substituents
described above and herein may be substituted or unsubstituted.
Additional examples of generally applicable substitutents are
illustrated by the specific embodiments shown in the Examples that
are described herein.
[0033] The term "cycloalkyl," as used herein, refers specifically
to groups having three to seven, preferably three to ten carbon
atoms. Suitable cycloalkyls include, but are not limited to
cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl and
the like, which, as in the case of other aliphatic,
heteroaliphatic, or hetercyclic moieties, may optionally be
substituted with substituents including, but not limited to
aliphatic; heteroaliphatic; aryl; heteroaryl; arylalkyl;
heteroarylalkyl; alkoxy; aryloxy; heteroalkoxy; heteroaryloxy;
alkylthio; arylthio; heteroalkylthio; heteroarylthio; --F; --Cl;
--Br; --I; --OH; --NO.sub.2; --CN; --CF.sub.3; --CH.sub.2CF.sub.3;
--CHCl.sub.2; --CH.sub.2OH; --CH.sub.2CH.sub.2OH;
--CH.sub.2NH.sub.2; --CH.sub.2SO.sub.2CH.sub.3; --C(O)R.sub.x;
--OC.sub.2(R.sub.x); --CON(R.sub.x).sub.2; --OC(O)R.sub.x;
--OCO.sub.2R.sub.x; --OCON(R.sub.x).sub.2; --N(R.sub.x).sub.2;
--S(O).sub.2R.sub.x; --NR.sub.x(CO)R.sub.x, wherein each occurrence
of R.sub.x independently includes, but is not limited to,
aliphatic, heteroaliphatic, aryl, heteroaryl, arylalkyl, or
heteroarylalkyl, wherein any of the aliphatic, heteroaliphatic,
arylalkyl, or heteroarylalkyl substituents described above and
herein may be substituted or unsubstituted, branched or unbranched,
cyclic or acyclic, and wherein any of the aryl or heteroaryl
substituents described above and herein may be substituted or
unsubstituted. Additional examples of generally applicable
substitutents are illustrated by the specific embodiments shown in
the Examples that are described herein.
[0034] The term "heteroaliphatic," as used herein, refers to
aliphatic moieties that contain one or more oxygen, sulfur,
nitrogen, phosphorus, or silicon atoms, e.g., in place of carbon
atoms. Heteroaliphatic moieties may be branched, unbranched, cyclic
or acyclic and include saturated and unsaturated heterocycles such
as morpholino, pyrrolidinyl, etc. In certain embodiments,
heteroaliphatic moieties are substituted by independent replacement
of one or more of the hydrogen atoms thereon with one or more
moieties including, but not limited to aliphatic; heteroaliphatic;
aryl; heteroaryl; arylalkyl; heteroarylalkyl; alkoxy; aryloxy;
heteroalkoxy; heteroaryloxy; alkylthio; arylthio; heteroalkylthio;
heteroarylthio; --F; --Cl; --Br; --I; --OH; --NO.sub.2; --CN;
--CF.sub.3; --CH.sub.2CF.sub.3; --CHCl.sub.2; --CH.sub.2OH;
--CH.sub.2CH.sub.2OH; --CH.sub.2NH.sub.2;
--CH.sub.2SO.sub.2CH.sub.3; --C(O)R.sub.x; --OC.sub.2(R.sub.x);
--CON(R.sub.x).sub.2; --OC(O)R.sub.x; --OCO.sub.2R.sub.x;
--OCON(R.sub.x).sub.2; --N(R.sub.x).sub.2; --S(O).sub.2R.sub.x;
--NR.sub.x(CO)R.sub.x, wherein each occurrence of R.sub.x
independently includes, but is not limited to, aliphatic,
heteroaliphatic, aryl, heteroaryl, arylalkyl, or heteroarylalkyl,
wherein any of the aliphatic, heteroaliphatic, arylalkyl, or
heteroarylalkyl substituents described above and herein may be
substituted or unsubstituted, branched or unbranched, cyclic or
acyclic, and wherein any of the aryl or heteroaryl substituents
described above and herein may be substituted or unsubstituted.
Additional examples of generally applicable substitutents are
illustrated by the specific embodiments shown in the Examples that
are described herein.
[0035] The term "haloalkyl" denotes an alkyl group, as defined
above, having one, two, or three halogen atoms attached thereto and
is exemplified by such groups as chloromethyl, bromoethyl,
trifluoromethyl, and the like.
[0036] The term "heterocycloalkyl" or "heterocycle," as used
herein, refers to a non-aromatic 5-, 6-, or 7-membered ring or a
polycyclic group, including, but not limited to a bi- or tri-cyclic
group comprising fused six-membered rings having between one and
three heteroatoms independently selected from oxygen, sulfur and
nitrogen, wherein (i) each 5-membered ring has 0 to 1 double bonds
and each 6-membered ring has 0 to 2 double bonds, (ii) the nitrogen
and sulfur heteroatoms may be optionally be oxidized, (iii) the
nitrogen heteroatom may optionally be quaternized, and (iv) any of
the above heterocyclic rings may be fused to a benzene ring.
Representative heterocycles include, but are not limited to,
pyrrolidinyl, pyrazolinyl, pyrazolidinyl, imidazolinyl,
imidazolidinyl, piperidinyl, piperazinyl, oxazolidinyl,
isoxazolidinyl, morpholinyl, thiazolidinyl, isothiazolidinyl, and
tetrahydrofuryl. In certain embodiments, a "substituted
heterocycloalkyl or heterocycle" group is utilized and as used
herein, refers to a heterocycloalkyl or heterocycle group, as
defined above, substituted by the independent replacement of one,
two or three of the hydrogen atoms thereon with but are not limited
to aliphatic; heteroaliphatic; aryl; heteroaryl; arylalkyl;
heteroarylalkyl; alkoxy; aryloxy; heteroalkoxy; heteroaryloxy;
alkylthio; arylthio; heteroalkylthio; heteroarylthio; --F; --Cl;
--Br; --I; --OH; --NO.sub.2; --CN; --CF.sub.3; --CH.sub.2CF.sub.3;
--CHCl.sub.2; --CH.sub.2OH; --CH.sub.2CH.sub.2OH;
--CH.sub.2NH.sub.2; --CH.sub.2SO.sub.2CH.sub.3; --C(O)R.sub.x;
--OC.sub.2(R.sub.x); --CON(R.sub.x).sub.2; --OC(O)R.sub.x;
--OCO.sub.2R.sub.x; --OCON(R.sub.x).sub.2; --N(R.sub.x).sub.2;
--S(O).sub.2R.sub.x; --NR.sub.x(CO)R.sub.x, wherein each occurrence
of R.sub.x independently includes, but is not limited to,
aliphatic, heteroaliphatic, aryl, heteroaryl, arylalkyl, or
heteroarylalkyl, wherein any of the aliphatic, heteroaliphatic,
arylalkyl, or heteroarylalkyl substituents described above and
herein may be substituted or unsubstituted, branched or unbranched,
cyclic or acyclic, and wherein any of the aryl or heteroaryl
substituents described above and herein may be substituted or
unsubstituted. Additional examples of generally applicable
substitutents are illustrated by the specific embodiments shown in
the Examples which are described herein.
[0037] The term "carbocycle," as used herein, refers to an aromatic
or non-aromatic ring in which each atom of the ring is a carbon
atom.
[0038] The term "independently selected" is used herein to indicate
that the R groups can be identical or different.
[0039] As used herein, the term "labeled" is intended to mean that
a compound has at least one element, isotope, or chemical compound
attached to enable the detection of the compound. In general,
labels typically fall into three classes: a) isotopic labels, which
may be radioactive or heavy isotopes, including, but not limited
to, .sup.2H, .sup.3H, .sup.32P, .sup.35S, .sup.67Ga, .sup.99mTc
(Tc-99m), .sup.111In, .sup.123I, .sup.125I, .sup.169Yb and
.sup.186Re; b) immune labels, which may be antibodies or antigens,
which may be bound to enzymes (such as horseradish peroxidase) that
produce detectable agents; and c) colored, luminescent,
phosphorescent, or fluorescent dyes. It will be appreciated that
the labels may be incorporated into the compound at any position
that does not interfere with the biological activity or
characteristic of the compound that is being detected. In certain
embodiments of the invention, photoaffinity labeling is utilized
for the direct elucidation of intermolecular interactions in
biological systems. A variety of known photophores can be employed,
most relying on photoconversion of diazo compounds, azides, or
diazirines to nitrenes or carbenes (See, Bayley, H., Photogenerated
Reagents in Biochemistry and Molecular Biology (1983), Elsevier,
Amsterdam.), the entire contents of which are hereby incorporated
by reference. In certain embodiments of the invention, the
photoaffinity labels employed are o-, m- and p-azidobenzoyls,
substituted with one or more halogen moieties, including, but not
limited to 4-azido-2,3,5,6-tetrafluorobenzoic acid.
[0040] The terms "halo" and "halogen" as used herein refer to an
atom selected from fluorine, chlorine, bromine, and iodine.
[0041] The term "heterocyclic," as used herein, refers to a
non-aromatic partially unsaturated or fully saturated 3- to
10-membered ring system, which includes single rings of 3 to 8
atoms in size and bi- and tri-cyclic ring systems which may include
aromatic six-membered aryl or aromatic heterocyclic groups fused to
a non-aromatic ring. These heterocyclic rings include those having
from one to three heteroatoms independently selected from oxygen,
sulfur, and nitrogen, in which the nitrogen and sulfur heteroatoms
may optionally be oxidized and the nitrogen heteroatom may
optionally be quaternized.
[0042] The term "heteroaryl," as used herein, refers to a cyclic
aromatic radical having from five to ten ring atoms of which one
ring atom is selected from sulfur, oxygen, and nitrogen; zero, one,
or two ring atoms are additional heteroatoms independently selected
from sulfur, oxygen, and nitrogen; and the remaining ring atoms are
carbon, the radical being joined to the rest of the molecule via
any of the ring atoms, such as, for example, pyridyl, pyrazinyl,
pyrimidinyl, pyrrolyl, pyrazolyl, imidazolyl, thiazolyl, oxazolyl,
isooxazolyl, thiadiazolyl, oxadiazolyl, thiophenyl, furanyl,
quinolinyl, isoquinolinyl, and the like.
[0043] Specific heterocyclic and aromatic heterocyclic groups that
may be included in the compounds of the invention include:
3-methyl-4-(3-methylphenyl)piperazine, 3 methylpiperidine,
4-(bis-(4-fluorophenyl)methyl)piperazine,
4-(diphenylmethyl)piperazine, 4-(ethoxycarbonyl)piperazine,
4-(ethoxycarbonylmethyl)piperazine, 4-(phenylmethyl)piperazine,
4-(1-phenylethyl)piperazine,
4-(1,1-dimethylethoxycarbonyl)piperazine,
4-(2-(bis-(2-propenyl)amino)ethyl)piperazine,
4-(2-(diethylamino)ethyl)piperazine, 4-(2-chlorophenyl)piperazine,
4-(2-cyanophenyl)piperazine, 4-(2-ethoxyphenyl)piperazine,
4-(2-ethylphenyl)piperazine, 4-(2-fluorophenyl)piperazine,
4-(2-hydroxyethyl)piperazine, 4-(2-methoxyethyl)piperazine,
4-(2-methoxyphenyl)piperazine, 4-(2-methylphenyl)piperazine,
4-(2-methylthiophenyl)piperazine, 4-(2-nitrophenyl)piperazine,
4-(2-nitrophenyl)piperazine, 4-(2-phenylethyl)piperazine,
4-(2-pyridyl)piperazine, 4-(2-pyrimidinyl)piperazine,
4-(2,3-dimethylphenyl)piperazine, 4-(2,4-difluorophenyl)piperazine,
4-(2,4-dimethoxyphenyl)piperazine,
4-(2,4-dimethylphenyl)piperazine, 4-(2,5-dimethylphenyl)piperazine,
4-(2,6-dimethylphenyl)piperazine, 4-(3-chlorophenyl)piperazine,
4-(3-methylphenyl)piperazine,
4-(3-trifluoromethylphenyl)piperazine,
4-(3,4-dichlorophenyl)piperazine, 4-3,4-dimethoxyphenyl)piperazine,
4-(3,4-dimethylphenyl)piperazine,
4-(3,4-methylenedioxyphenyl)piperazine,
4-(3,4,5-trimethoxyphenyl)piperazine,
4-(3,5-dichlorophenyl)piperazine,
4-(3,5-dimethoxyphenyl)piperazine,
4-(4-(phenylmethoxy)phenyl)piperazine,
4-(4-(3,1-dimethylethyl)phenylmethyl)piperazine,
4-(4-chloro-3-trifluoromethylphenyl)piperazine,
4-(4-chlorophenyl)-3-methylpiperazine,
4-(4-chlorophenyl)piperazine, 4-(4-chlorophenyl)piperazine,
4-(4-chlorophenylmethyl)piperazine, 4-(4-fluorophenyl)piperazine,
4-(4-methoxyphenyl)piperazine, 4-(4-methylphenyl)piperazine,
4-(4-nitrophenyl)piperazine, 4-(4-trifluoromethylphenyl)piperazine,
4-cyclohexylpiperazine, 4-ethylpiperazine,
4-hydroxy-4-(4-chlorophenyl)methylpiperidine,
4-hydroxy-4-phenylpiperidine, 4-hydroxypyrrolidine,
4-methylpiperazine, 4-phenylpiperazine, 4-piperidinylpiperazine,
4-(2-furanyl)carbonyl)piperazine,
4-((1,3-dioxolan-5-yl)methyl)piperazine,
6-fluoro-1,2,3,4-tetrahydro-2-methylquinoline,
1,4-diazacylcloheptane, 2,3-dihydroindolyl, 3,3-dimethylpiperidine,
4,4-ethylenedioxypiperidine, 1,2,3,4-tetrahydroisoquinoline,
1,2,3,4-tetrahydroquinoline, azacyclooctane, decahydroquinoline,
piperazine, piperidine, pyrrolidine, thiomorpholine, and
triazole.
[0044] The term "substituted," whether preceded by the term
"optionally" or not, and "substituent," as used herein, refer to
the ability, as appreciated by one skilled in this art, to change
one functional group for another functional group provided that the
valency of all atoms is maintained. When more than one position in
any given structure may be substituted with more than one
substituent selected from a specified group, the substituent may be
either the same or different at every position. The substituents
may also be further substituted (e.g., an aryl group substituent
may have another substituent off it, such as another aryl group,
which is further substituted with fluorine at one or more
positions).
[0045] The following are more general terms used throughout the
present application:
[0046] "Animal": The term animal, as used herein, refers to humans
as well as non-human animals, including, for example, mammals,
birds, reptiles, amphibians, and fish. Preferably, the non-human
animal is a mammal (e.g., a rodent, a mouse, a rat, a rabbit, a
monkey, a dog, a cat, a primate, or a pig). An animal may be a
transgenic animal.
[0047] "Associated with": When two entities are "associated with"
one another as described herein, they are linked by a direct or
indirect covalent or non-covalent interaction. Preferably, the
association is covalent. Desirable non-covalent interactions
include hydrogen bonding, van der Waals interactions, hydrophobic
interactions, magnetic interactions, electrostatic interactions,
etc. In certain embodiments, an poly(beta-amino alcohols) is
associated with a polynucleotide through electrostatic
interactions.
[0048] "Biocompatible": The term "biocompatible," as used herein is
intended to describe compounds that are not toxic to cells.
Compounds are "biocompatible" if their addition to cells in vitro
results in less than or equal to 20% cell death, and their
administration in vivo does not induce inflammation or other such
adverse effects.
[0049] "Biodegradable": As used herein, "biodegradable" compounds
are those that, when introduced into cells, are broken down by the
cellular machinery or by hydrolysis into components that the cells
can either reuse or dispose of without significant toxic effect on
the cells (i.e., fewer than about 20% of the cells are killed when
the components are added to cells in vitro). The components
preferably do not induce inflammation or other adverse effects in
vivo. In certain embodiments, the chemical reactions relied upon to
break down the biodegradable compounds are uncatalyzed.
[0050] "Effective amount": In general, the "effective amount" of an
active agent or composition refers to the amount necessary to
elicit the desired biological response. As will be appreciated by
those of ordinary skill in this art, the effective amount of an
agent or device may vary depending on such factors as the desired
biological endpoint, the agent to be delivered, the composition of
the encapsulating matrix, the target tissue, etc. For example, the
effective amount of microparticles containing an antigen to be
delivered to immunize an individual is the amount that results in
an immune response sufficient to prevent infection with an organism
having the administered antigen.
[0051] "Medical device" and "implant": As used herein, the terms
"medical device" and "implant" refer to any object that is designed
to be placed partially or wholly within a patient's body for one or
more therapeutic or prophylactic purposes such as for restoring
physiological function, alleviating symptoms associated with a
disease, delivering therapeutic agents, and/or repairing,
replacing, or augmenting damaged or diseased organs and tissues.
While normally composed of biologically compatible synthetic
materials (e.g., medical-grade stainless steel, titanium, and other
metals; polymers such as polyurethane, silicon, PLA, PLGA, and
other materials) that are exogenous, some medical devices and
implants include materials derived from animals (e.g., "xenografts"
such as whole animal organs; animal tissues such as heart valves;
naturally occurring or chemically-modified molecules such as
collagen; hyaluronic acid, proteins, carbohydrates and others),
human donors (e.g., "allografts" such as whole organs; tissues such
as bone grafts, skin grafts and others), or from the patients
themselves (e.g., "autografts" such as saphenous vein grafts, skin
grafts, tendon/ligament/muscle transplants). Medical devices of
particular utility in the present invention include, but are not
restricted to, vascular stents, gastrointestinal stents,
tracheal/bronchial stents, genital-urinary stents, ENT stents,
intraocular lenses, implants for hypertrophic scars and keloids,
vascular grafts, anastomotic connector devices, surgical adhesion
barriers, glaucoma drainage devices, film or mesh, prosthetic heart
valves, tympanostomy tubes, penile implants, endotracheal and
tracheostomy tubes, peritoneal dialysis catheters, intracranial
pressure monitors, vena cava filters, CVCs, ventricular assist
device (e.g., LVAD), spinal prostheses, and gastrointestinal
drainage tubes.
[0052] A wide variety of implants and devices can be coated with or
otherwise constructed to contain and/or release the poly(beta-amino
alcohols) provided herein. Representative examples include
cardiovascular devices (e.g., implantable venous catheters, venous
ports, tunneled venous catheters, chronic infusion lines or ports,
including hepatic artery infusion catheters, pacemakers and
pacesmaker leads (see, e.g., U.S. Pat. Nos. 4,662,382, 4,782,836,
4,856,521, 4,860,751, 5,101,824, 5,261,419, 5,284,491, 6,055,454,
6,370,434, and 6,370,434, the entire contents of which are hereby
incorporated by reference), implantable defibrillators (see, e.g.,
U.S. Pat. Nos. 3,614,954, 3,614,955, 4,375,817, 5,314,430,
5,405,363, 5,607,385, 5,697,953, 5,776,165, 6,067,471, 6,169,923,
and 6,152,955, the entire contents of which are hereby incorporated
by reference)); neurologic/neurosurgical devices (e.g., ventricular
peritoneal shunts, ventricular atrial shunts, nerve stimulator
devices, dural patches and implants to prevent epidural fibrosis
post-laminectomy, devices for continuous subarachnoid infusions);
gastrointestinal devices (e.g., chronic indwelling catheters,
feeding tubes, portosystemic shunts, shunts for ascites, peritoneal
implants for drug delivery, peritoneal dialysis catheters, and
suspensions or solid implants to prevent surgical adhesions);
genitourinary devices (e.g., uterine implants, including
intrauterine devices (IUDs) and devices to prevent endometrial
hyperplasia, fallopian tubal implants, including reversible
sterilization devices, fallopian tubal stents, artificial
sphincters and periurethral implants for incontinence, ureteric
stents, chronic indwelling catheters, bladder augmentations, or
wraps or splints for vasovasostomy, central venous catheters (see,
e.g., U.S. Pat. Nos. 3,995,623, 4,072,146 4,096,860, 4,099,528,
4,134,402, 4,180,068, 4,385,631, 4,406,656, 4,568,329, 4,960,409,
5,176,661, 5,916,208, the entire contents of which are hereby
incorporated by reference), urinary catheters (see, e.g. U.S. Pat.
Nos. 2,819,718, 4,227,533, 4,284,459, 4,335,723, 4,701,162,
4,571,241, 4,710,169, and 5,300,022, the entire contents of which
are hereby incorporated by reference.)); prosthetic heart valves
(see, e.g., U.S. Pat. Nos. 3,656,185, 4,106,129, 4,892,540,
5,528,023, 5,772,694, 6,096,075, 6,176,877, 6,358,278, and
6,371,983, the entire contents of which are hereby incorporated by
reference), vascular grafts (see, e.g., U.S. Pat. Nos. 3,096,560,
3,805,301, 3,945,052, 4,140,126, 4,323,525, 4,355,426, 4,475,972,
4,530,113, 4,550,447, 4,562,596, 4,601,718, 4,647,416, 4,878,908,
5,024,671, 5,104,399, 5,116,360, 5,151,105, 5,197,977, 5,282,824,
5,405,379, 5,609,624, 5,693,088, and 5,910,168, the entire contents
of which are hereby incorporated by reference), opthalmologic
implants (e.g., multino implants and other implants for neovascular
glaucoma, drug eluting contact lenses for pterygiums, splints for
failed dacrocystalrhinostomy, drug eluting contact lenses for
corneal neovascularity, implants for diabetic retinopathy, drug
eluting contact lenses for high risk corneal transplants);
otolaryngology devices (e.g., ossicular implants, Eustachian tube
splints or stents for glue ear or chronic otitis as an alternative
to transtempanic drains); plastic surgery implants (e.g., breast
implants or chin implants), catheter cuffs and orthopedic implants
(e.g., cemented orthopedic prostheses).
[0053] Further examples of such implants or devices which can be
coated with or otherwise constructed to contain and/or release the
inventive poly(beta-amino alcohols) include vascular stents,
gastrointestinal stents, tracheal/bronchial stents, genital-urinary
stents, ENT stents, intraocular lenses, implants for hypertrophic
scars and keloids, vascular grafts, anastomotic connector devices,
surgical adhesion barriers, glaucoma drainage devices, prosthetic
heart valves, tympanostomy tubes, penile implants, CVCs,
ventricular assist devices (e.g., LVAD's), spinal prostheses,
endotracheal and tracheostomy tubes, peritoneal dialysis catheters,
intracranial pressure monitors, vena cava filters, and
gastrointestinal drainage tubes.
[0054] "Peptide" or "protein": According to the present invention,
a "peptide" or "protein" comprises a string of at least three amino
acids linked together by peptide bonds. The terms "protein" and
"peptide" may be used interchangeably. Peptide may refer to an
individual peptide or a collection of peptides. Inventive peptides
preferably contain only natural amino acids, although non-natural
amino acids (i.e., compounds that do not occur in nature but that
can be incorporated into a polypeptide chain) and/or amino acid
analogs as are known in the art may alternatively be employed.
Also, one or more of the amino acids in an inventive peptide may be
modified, for example, by the addition of a chemical entity such as
a carbohydrate group, a phosphate group, a farnesyl group, an
isofarnesyl group, a fatty acid group, a linker for conjugation,
functionalization, or other modification, etc. In certain
embodiments, the modifications of the peptide lead to a more stable
peptide (e.g., greater half-life in vivo). These modifications may
include cyclization of the peptide, the incorporation of D-amino
acids, etc. None of the modifications should substantially
interfere with the desired biological activity of the peptide.
[0055] "Polynucleotide" or "oligonucleotide": Polynucleotide or
oligonucleotide refers to a polymer of nucleotides. Typically, a
polynucleotide comprises at least three nucleotides. The polymer
may include natural nucleosides (i.e., adenosine, thymidine,
guanosine, cytidine, uridine, deoxyadenosine, deoxythymidine,
deoxyguanosine, and deoxycytidine), nucleoside analogs (e.g.,
2-aminoadenosine, 2-thiothymidine, inosine, pyrrolo-pyrimidine,
3-methyl adenosine, C5-propynylcytidine, C5-propynyluridine,
C5-bromouridine, C5-fluorouridine, C5-iodouridine,
C5-methylcytidine, 7-deazaadenosine, 7-deazaguanosine,
8-oxoadenosine, 8-oxoguanosine, O(6)-methylguanine, and
2-thiocytidine), chemically modified bases, biologically modified
bases (e.g., methylated bases), intercalated bases, modified sugars
(e.g., 2'-fluororibose, ribose, 2'-deoxyribose, arabinose, and
hexose), or modified phosphate groups (e.g., phosphorothioates and
5'-N-phosphoramidite linkages).
[0056] "Small molecule": As used herein, the term "small molecule"
refers to organic compounds, whether naturally-occurring or
artificially created (e.g., via chemical synthesis) that have
relatively low molecular weight and that are not proteins,
polypeptides, or nucleic acids. Typically, small molecules have a
molecular weight of less than about 1500 g/mol. In certain
embodiments, the small molecule is uncharged. In certain
embodiments, the small molecule is negatively charged. Also, small
molecules typically have multiple carbon-carbon bonds. Known
naturally-occurring small molecules include, but are not limited
to, penicillin, erythromycin, taxol, cyclosporin, and rapamycin.
Known synthetic small molecules include, but are not limited to,
ampicillin, methicillin, sulfamethoxazole, and sulfonamides.
[0057] "Step-growth polymerization": As used herein, the term
"step-growth polymerization" refers to a type of polymerization
mechanism in which bi-functional or multifunctional monomers react
to form first dimers, then trimers, longer oligomers and eventually
long chain polymers. Many naturally occurring and some synthetic
polymers are produced by step-growth polymerization (e.g.
polyesters, polyamides, polyurethanes, etc.) Due to the nature of
the polymerization mechanism, a high extent of reaction is required
to achieve high molecular weight. The easiest way to visualize the
mechanism of a step-growth polymerization is a group of people
reaching out to hold their hands to form a human chain--each person
has two hands (i.e., reactive sites). There also is the possibility
of having more than two reactive sites on a monomer. In such a case
branched polymers are produced.
BRIEF DESCRIPTION OF THE DRAWINGS
[0058] FIGS. 1A to 1C depict the in vitro screening of PBAAs for
biocompatible coatings using monocyte/macrophage cells. (FIG. 1A)
The dependence of TNF-.alpha. concentration on surface chemistry.
The control is the uncoated glass surface. SEM images show the
morphological differences of the cells between uncoated surface
(FIG. 1B) and B20-coated surface (FIG. 1C). Insets show the
morphologies of single cells.
[0059] FIGS. 2A to 2E depict the cell viability and
characterization of the PBAA coatings. (FIG. 2A) The dependence of
relative absorbance on different PBAA coatings. Optical images show
live staining of the cells on uncoated (FIG. 2B) and B20-coated
surfaces (FIG. 2C). (FIG. 2D) The concentrations of TNF-.alpha.
secreted by cells on normal coatings, presoaked surfaces and
uncoated surfaces with pre-conditioned media. (FIG. 2E) XPS of
uncoated surface (bottom), B20 coated surface (top) and B20 coated
surface soaked in PBS for 24 hours (middle).
[0060] FIGS. 3A to 3E depict the imaging of live animals with
subcutaneously-injected PBAA-coated microparticles. (FIG. 3A) SEM
image of carboxylated polystyrene beads used as the substrate for
PBAA coatings. The inset is the schematic of the PBAA coating on
the particles (not to scale). (FIG. 3B) Chemical structures of A12
and B35, which promote or inhibit the activation of
monocyte/macrophage cells in vitro, respectively. (FIG. 3C) The
configuration of six injections on the back of a mouse. (FIG. 3D)
Fluorescent images of mice (five replicates) 24 hours after
injections using Prosense 750 as the probe and quantitative results
from the image analysis. (FIG. 3E) Luminescent image of the same
five mice using Luminol as the probe and quantitative results.
[0061] FIGS. 4A to 4C depict Masson's trichrome stained skin
tissues containing subcutaneously injected particles 30 days after
injection. (FIG. 4A) uncoated particles; (FIG. 4B) A12 coated
particles and (FIG. 4C) B35 coated particles. The images on the
right are magnifications of the enclosed regions of the images on
the left. The white spheres in the images are the 20 .mu.m
particles. Note that many particles detached during the sample
preparation in the cases of (FIG. 4A) and (FIG. 4B).
DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS OF THE INVENTION
[0062] Combinatorial polymerization was used to synthesize a new
class of novel cationic polymers, poly(beta-amino alcohols)
(PBAAs). The synthesized polymers covered a wide range of chemical
functionality and can be easily applied as a coating for the study
of surface chemistry effects on the foreign body response. An
initial in vitro screening was used to identify the polymer
coatings that promoted or inhibited the activation of mouse
monocyte/macrophage cells by measuring the secretion of a
pro-inflammatory cytokine, tumor necrosis factor-.alpha.
(TNF-.alpha.). The polymer coatings that induced the highest and
lowest levels of TNF-.alpha. secretion were used to coat
carboxylated polystyrene microparticles which were subsequently
injected into mice subcutaneously. Twenty-four hours after the
injections significantly different levels of inflammatory cell
recruitment into the implantation sites were observed using live
animal imaging. Histological analysis of the fibrosis around the
particles 30 days after injections showed correlation with both the
in vitro and live imaging results.
Poly(Beta-Amino Alcohols) (PBAA)
[0063] The poly(beta-amino alcohols) of the present invention are
poly(beta-amino alcohols) containing primary, secondary, tertiary,
and/or quaternary amines, and salts thereof. In certain
embodiments, the inventive poly(beta-amino alcohols) are relatively
non-cytotoxic. In another embodiment, the inventive poly(beta-amino
alcohosl) are biocompatible and biodegradable. In certain
embodiments, the poly(beta-amino alcohols) of the present invention
have pK.sub.as in the range of approximately 5.5 to approximately
7.5, more preferably between approximately 6.0 and approximately
7.0. In another embodiment, the poly(beta-amino alcohols) may be
designed to have a desired pK.sub.a between approximately 3.0 and
approximately 9.0, or between approximately 5.0 and approximately
8.0.
[0064] The inventive poly(beta-amino alcohols) may be used in
biotechnology and biomedical applications as coatings (such as
coatings of films or multilayer films for medical devices or
implants), additives, materials, excipients, non-biofouling agents,
micropatterning agents, and cellular encapsulation agents. The
inventive polymers may be used for other purposes as well such as,
for example, the administration and/or delivery of therapeutic
agents (e.g., polynucleotide, small molecule, antigen, drug,
protein, peptide, etc.) to a subject, patient, tissue, organ, or
cell, etc. The inventive poly(beta-amino alcohols) are particularly
attractive for drug delivery for several reasons: 1) they contain
amino groups for interacting with DNA, RNA, other polynucleotides,
and other negatively charged agents, for buffering the pH, for
causing endosomolysis, for protecting the agent to be delivered,
etc.; 2) they can be synthesized from commercially available
starting materials; and/or 3) they are pH responsive and can be
engineered with a desired pK.sub.a.
[0065] In certain embodiments, the poly(beta-amino alcohols) are
prepared by reacting an amine with a diepoxide according to the
following schemes:
##STR00010##
wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, A, B, n, E,
and G are as defined herein.
[0066] In certain embodiments, the diepoxide is stereochemically
pure (e.g., enantiomerically pure). In certain embodiments, the
amine is stereochemically pure (e.g., enantiomerically pure). As
will be appreciated by one of skill in the art, the amine may be
reacted with an excess of diepoxide to form a fully functionalized
poly(beta-amino alcohols). Or, the poly(beta-amino alcohols) may be
prepared from an excess of amino functional groups relative to
epoxide functional groups.
[0067] The poly(beta-amino alcohols) of the present invention is of
the formula:
##STR00011##
wherein:
[0068] each A and B is, independently, a bond; a substituted or
unsubstituted, branched or unbranched, cyclic or acyclic C.sub.1-20
aliphatic; a substituted or unsubstituted, branched or unbranched,
cyclic or acyclic C.sub.1-20 heteroaliphatic; substituted or
unsubstituted aryl; or a substituted or unsubstituted
heteroaryl;
[0069] each R.sup.1 and R.sup.2 is, independently, hydrogen; a
substituted or unsubstituted, branched or unbranched, cyclic or
acyclic C.sub.1-20 aliphatic; a substituted or unsubstituted,
branched or unbranched, cyclic or acyclic C.sub.1-20
heteroaliphatic; substituted or unsubstituted aryl; or a
substituted or unsubstituted heteroaryl;
[0070] each
##STR00012##
may optionally form a cyclic structure by the joining of R.sup.1
and R.sup.2;
[0071] each R.sup.3, R.sup.4, and R.sup.5 is hydrogen; a
substituted or unsubstituted, branched or unbranched, cyclic or
acyclic C.sub.1-20 aliphatic; a substituted or unsubstituted,
branched or unbranched, cyclic or acyclic C.sub.1-20
heteroaliphatic; a substituted or unsubstituted aryl; or a
substituted or unsubstituted heteroaryl;
[0072] each
##STR00013##
may optionally form a cyclic structure;
[0073] each E and G is, independently, hydrogen; a substituted or
unsubstituted, branched or unbranched, cyclic or acyclic C.sub.1-20
aliphatic; a substituted or unsubstituted, branched or unbranched,
cyclic or acyclic C.sub.1-20 heteroaliphatic; substituted or
unsubstituted aryl; a substituted or unsubstituted heteroaryl;
A
##STR00014##
n is an integer from 2 to 10,000, inclusive; or a salt thereof.
[0074] In certain embodiments, A is substituted or unsubstituted,
branched or unbranched, cyclic or acyclic C.sub.1-20 aliphatic. In
certain embodiments, A is substituted or unsubstituted, branched or
unbranched, cyclic or acyclic C.sub.1-20 heteroaliphatic. In
certain embodiments, A is a substituted or unsubstituted aryl. In
certain embodiments, A is a substituted or unsubstituted
heteroaryl. In certain embodiments, A is substituted or
unsubstituted, branched or unbranched, cyclic or acyclic C.sub.1-20
alkylene. In certain embodiments, A is selected from the group
consisting of:
##STR00015## ##STR00016##
wherein
[0075] each R.sup.10 is, independently, hydrogen; a substituted or
unsubstituted, branched or unbranched, cyclic or acyclic C.sub.1-20
aliphatic; a substituted or unsubstituted, branched or unbranched,
cyclic or acyclic C.sub.1-20 heteroaliphatic; substituted or
unsubstituted aryl; a substituted or unsubstituted heteroaryl; or
an N-protecting group; and
[0076] each q is, independently, an integer between 0 and 10,
inclusive.
[0077] In certain embodiments,
##STR00017##
is selected from the group consisting of:
##STR00018##
[0078] In certain embodiments, B is substituted or unsubstituted,
branched or unbranched, cyclic or acyclic C.sub.1-20 aliphatic. In
certain embodiments, B is substituted or unsubstituted, branched or
unbranched, cyclic or acyclic C.sub.1-20 heteroaliphatic. In
certain embodiments, B is a substituted or unsubstituted aryl. In
certain embodiments, B is a substituted or unsubstituted
heteroaryl. In certain embodiments, B is substituted or
unsubstituted, branched or unbranched, cyclic or acyclic C.sub.1-20
alkylene. In certain embodiments, B is selected from the group
consisting of:
a bond,
##STR00019## ##STR00020##
wherein each q is, independently, an integer between 0 and 10,
inclusive.
[0079] In certain embodiments, each R.sup.1 and R.sup.2 is
independently substituted or unsubstituted, branched or unbranched,
cyclic or acyclic C1-20 aliphatic. In certain embodiments, each
R.sup.1 and R.sup.2 is independently substituted or unsubstituted,
branched or unbranched, cyclic or acyclic C.sub.1-20
heteroaliphatic. In certain embodiments, each R.sup.1 and R.sup.2
is independently a substituted or unsubstituted aryl. In certain
embodiments, each R.sup.2 and R.sup.2 is independently a
substituted or unsubstituted heteroaryl. In certain embodiments,
each R.sup.1 and R.sup.2 is independently substituted or
unsubstituted, branched or unbranched, cyclic or acyclic C.sub.1-20
alkylene. In certain embodiments, R.sup.1 and R.sup.2 are the same.
In certain embodiments, R.sup.1 and R.sup.2 are different. In
certain embodiments, each R.sup.1 and R.sup.2 are all hydrogen or
all C.sub.1-C.sub.6 alkyl. In certain embodiments, each R.sup.1 and
R.sup.2 are all hydrogen. In certain embodiments, each R.sup.1 and
R.sup.2 are all C.sub.1-C.sub.6 alkyl. In certain embodiments, each
R.sup.1 and R.sup.2 are all hydroxyalkyl. In certain embodiments,
each R.sup.1 and R.sup.2 are all aminoalkyl. In certain
embodiments, each R.sup.1 and R.sup.2 are hydrogen or methyl. In
certain embodiments, each R.sup.1 and R.sup.2 is independently
selected from the group consisting of:
##STR00021##
[0080] In certain embodiments, each R.sup.3, R.sup.4, and R.sup.5
is hydrogen or an independently substituted or unsubstituted,
branched or unbranched, cyclic or acyclic C.sub.1-20 aliphatic. In
certain embodiments, each R.sup.3, R.sup.4, and R.sup.5 is hydrogen
or an independently branched C.sub.1-C.sub.20 aliphatic. In certain
embodiments, each R.sup.3, R.sup.4, and R.sup.5 is hydrogen or an
independently unbranched C.sub.1-C.sub.20 aliphatic. In certain
embodiments, each R.sup.3, R.sup.4, and R.sup.5 is hydrogen or an
independently fluorinated C.sub.1-C.sub.20 aliphatic. In certain
embodiments, each R.sup.3, R.sup.4, and R.sup.5 is hydrogen or an
independently substituted or unsubstituted, branched or unbranched,
cyclic or acyclic C.sub.1-20 heteroaliphatic. In certain
embodiments, each R.sup.3, R.sup.4, and R.sup.5 is hydrogen or an
independently substituted or unsubstituted aryl. In certain
embodiments, each R.sup.3, R.sup.4, and R.sup.5 is hydrogen or an
independently substituted or unsubstituted heteroaryl. In certain
embodiments, each R.sup.3, R.sup.4, and R.sup.5 is hydrogen or an
independently substituted or unsubstituted, branched or unbranched,
cyclic or acyclic C.sub.1-20 alkyl. In certain embodiments, each
R.sup.3, R.sup.4, and R.sup.5 is hydrogen or an independently
substituted or unsubstituted, cyclic or acyclic, branched or
unbranched C.sub.1-C.sub.15 alkyl. In certain embodiments, each
R.sup.3, R.sup.4, and R.sup.5 is hydrogen or an independently
substituted or unsubstituted, cyclic or acyclic, branched or
unbranched C.sub.1-C.sub.10 alkyl. In certain embodiments, each
R.sup.3, R.sup.4, and R.sup.5 is hydrogen or an independently
substituted or unsubstituted, cyclic or acyclic, branched or
unbranched C.sub.1-C.sub.5 alkyl.
[0081] In certain embodiments, all R.sup.3 and R.sup.4 are not
hydrogen. In certain embodiments, all R.sup.3 and R.sup.4 are
hydrogen. In certain embodiments, all R.sup.3, R.sup.4, and R.sup.5
are not hydrogen. In certain embodiments, all R.sup.3, R.sup.4, and
R.sup.5 are hydrogen. In certain embodiments, R.sup.5 is
hydrogen.
[0082] In certain embodiments, each R.sup.3, R.sup.4, and R.sup.5
is independently selected from the group consisting of:
##STR00022##
[0083] In certain embodiments, each R.sup.3, R.sup.4, and R.sup.5
is independently hydrogen or a substituted or unsubstituted, cyclic
or acyclic, branched or unbranched C.sub.1-C.sub.20 alkenyl. In
certain embodiments, each R.sup.3, R.sup.4, and R.sup.5 is
independently selected from the group consisting of:
##STR00023##
[0084] In certain embodiments, each R.sup.3, R.sup.4, and R.sup.5
is independently selected from the group consisting of:
##STR00024##
[0085] In certain embodiments, each R.sup.3, R.sup.4, and R.sup.5
is independently selected from the group consisting of:
##STR00025##
[0086] In certain embodiments, each
##STR00026##
is selected from the group consisting of:
##STR00027##
[0087] In certain embodiments, the molecular weight ranges between
1,000 and 100,000 Daltons. In certain embodiments, the molecular
weight ranges between 3,000 and 70,000 Daltons. In certain
embodiments, the molecular weight ranges between 5,000 and 40,000
Daltons. In certain embodiments, the molecular weight ranges
between 5,000 and 30,000 Daltons. In certain embodiments, the
molecular weight ranges between 5,000 and 20,000 Daltons. In
certain embodiments, the molecular weight ranges between 10,000 and
20,000 Daltons.
[0088] In certain embodiments, the polymer has at least one
secondary amine functional group in every repeating unit. In
certain embodiments, the polymer has at least one tertiary amine
functional group in every repeating unit. In certain embodiments,
the polymer has at least one quaternary amine functional group in
every repeating unit.
[0089] In certain embodiments, the polymer is linear. In certain
embodiments, the polymer is branched. In certain embodiments, the
polymer is dendritic. In certain embodiments, the polymer is not
water soluble. In certain embodiments, the polymer is
biodegradable.
[0090] In certain embodiments, the polymer is water-soluble. In
certain embodiments, the polymer is hydrolytically stable. In
certain embodiments, the polymer is not biodegradable. In certain
embodiments, less than 25% of the polymer is degraded after one
year in vivo. In certain embodiments, less than 10% of the polymer
is degraded after one year in vivo. In certain embodiments, less
than 5% of the polymer is degraded after one year in vivo. In
certain embodiments, less than 1% of the polymer is degraded after
one year in vivo. In certain embodiments, less than 25% of the
polymer is degraded after five years in vivo. In certain
embodiments, less than 10% of the polymer is degraded after five
years in vivo. In certain embodiments, less than 5% of the polymer
is degraded after five years in vivo. In certain embodiments, less
than 1% of the polymer is degraded after five years in vivo.
[0091] In some aspects, the poly(beta-amino alcohols) of the
present invention is prepared from a diepoxide selected from the
group consisting of:
##STR00028## ##STR00029##
wherein each q is, independently, an integer between 0 and 10,
inclusive.
[0092] In some aspects, the poly(beta-amino alcohols) of the
present invention is prepared from a diepoxide selected from the
group consisting of:
##STR00030## ##STR00031##
wherein each q is, independently, an integer between 0 and 10,
inclusive; and an amine selected from the group consisting of:
##STR00032## ##STR00033## ##STR00034## ##STR00035##
##STR00036##
[0093] In certain embodiments, the poly(beta-amino alcohol) is
selected from the group consisting of: F18, C01, F28, E19, B20,
D19, A03, A01, F12, A28, B19, A19, B01, A20, F19, F10, F20, B12,
A10, and A12. In certain embodiments, the polymer is selected from
the group consisting of: A10, A12, B12, and B20.
[0094] In some aspects, the poly(beta-amino alcohols) of the
present invention is of the formula:
##STR00037##
wherein:
[0095] B is a bond; a substituted or unsubstituted, branched or
unbranched, cyclic or acyclic C.sub.1-20 aliphatic; a substituted
or unsubstituted, branched or unbranched, cyclic or acyclic
C.sub.1-20 heteroaliphatic; substituted or unsubstituted aryl; or a
substituted or unsubstituted heteroaryl;
[0096] R.sup.2 is hydrogen; a substituted or unsubstituted,
branched or unbranched, cyclic or acyclic C.sub.1-20 aliphatic; a
substituted or unsubstituted, branched or unbranched, cyclic or
acyclic C.sub.1-20 heteroaliphatic; substituted or unsubstituted
aryl; or a substituted or unsubstituted heteroaryl;
[0097] each R.sup.3 and R.sup.4 is hydrogen, a substituted or
unsubstituted, branched or unbranched, cyclic or acyclic C.sub.1-20
aliphatic; a substituted or unsubstituted, branched or unbranched,
cyclic or acyclic C.sub.1-20 heteroaliphatic; a substituted or
unsubstituted aryl; or a substituted or unsubstituted
heteroaryl;
each
##STR00038##
may optionally form a cyclic structure; each E and G is,
independently, hydrogen, C.sub.1-C.sub.6 alkyl,
##STR00039##
n is an integer from 2 to 10,000, inclusive; or a salt thereof.
[0098] In certain embodiments, B is substituted or unsubstituted,
branched or unbranched, cyclic or acyclic C.sub.1-20 aliphatic. In
certain embodiments, B is substituted or unsubstituted, branched or
unbranched, cyclic or acyclic C.sub.1-20 heteroaliphatic. In
certain embodiments, B is a substituted or unsubstituted aryl. In
certain embodiments, B is a substituted or unsubstituted
heteroaryl. In certain embodiments, B is substituted or
unsubstituted, branched or unbranched, cyclic or acyclic C.sub.1-20
alkylene. In certain embodiments, B is selected from the group
consisting of:
##STR00040## ##STR00041##
wherein each q is, independently, an integer between 0 and 10,
inclusive.
[0099] In certain embodiments, R.sup.2 is substituted or
unsubstituted, branched or unbranched, cyclic or acyclic C.sub.1-20
aliphatic. In certain embodiments, R.sup.2 is substituted or
unsubstituted, branched or unbranched, cyclic or acyclic C.sub.1-20
heteroaliphatic. In certain embodiments, R.sup.2 is substituted or
unsubstituted aryl. In certain embodiments, R.sup.2 is substituted
or unsubstituted heteroaryl. In certain embodiments, R.sup.2 is
substituted or unsubstituted, branched or unbranched, cyclic or
acyclic C.sub.1-20 alkylene. In certain embodiments, R.sup.2 is
C.sub.1-C.sub.6 alkyl. In certain embodiments, R.sup.2 is
hydroxyalkyl. In certain embodiments, R.sup.2 is aminoalkyl. In
certain embodiments, R.sup.2 is methyl. In certain embodiments,
R.sup.2 is hydrogen. In certain embodiments, R.sup.2 is selected
from the group consisting of:
##STR00042##
[0100] In certain embodiments, each R.sup.3, R.sup.4, and R.sup.5
is hydrogen or an independently substituted or unsubstituted,
branched or unbranched, cyclic or acyclic C.sub.1-20 aliphatic. In
certain embodiments, each R.sup.3, R.sup.4, and R.sup.5 is hydrogen
or an independently branched C.sub.1-C.sub.20 aliphatic. In certain
embodiments, each R.sup.3, R.sup.4, and R.sup.5 is hydrogen or an
independently unbranched C.sub.1-C.sub.20 aliphatic. In certain
embodiments, each R.sup.3, R.sup.4, and R.sup.5 is hydrogen or an
independently fluorinated C.sub.1-C.sub.20 aliphatic. In certain
embodiments, each R.sup.3, R.sup.4, and R.sup.5 is hydrogen or an
independently substituted or unsubstituted, branched or unbranched,
cyclic or acyclic C.sub.1-20 heteroaliphatic. In certain
embodiments, each R.sup.3, R.sup.4, and R.sup.5 is hydrogen or an
independently substituted or unsubstituted aryl. In certain
embodiments, each R.sup.3, R.sup.4, and R.sup.5 is hydrogen or an
independently substituted or unsubstituted heteroaryl. In certain
embodiments, each R.sup.3, R.sup.4, and R.sup.5 is hydrogen or an
independently substituted or unsubstituted, branched or unbranched,
cyclic or acyclic C.sub.1-20 alkyl. In certain embodiments, each
R.sup.3, R.sup.4, and R.sup.5 is hydrogen or an independently
substituted or unsubstituted, cyclic or acyclic, branched or
unbranched C.sub.1-C.sub.15 alkyl. In certain embodiments, each
R.sup.3, R.sup.4, and R.sup.5 is hydrogen or an independently
substituted or unsubstituted, cyclic or acyclic, branched or
unbranched C.sub.1-C.sub.10 alkyl. In certain embodiments, each
R.sup.3, R.sup.4, and R.sup.5 is hydrogen or an independently
substituted or unsubstituted, cyclic or acyclic, branched or
unbranched C.sub.1-C.sub.6 alkyl.
[0101] In certain embodiments, all R.sup.3 and R.sup.4 are not
hydrogen. In certain embodiments, all R.sup.3 and R.sup.4 are
hydrogen. In certain embodiments, all R.sup.3, R.sup.4, and R.sup.5
are not hydrogen. In certain embodiments, all R.sup.3, R.sup.4, and
R.sup.5 are hydrogen. In certain embodiments, R.sup.5 is hydrogen.
In certain embodiments, each R.sup.3, R.sup.4, and R.sup.5 is
independently selected from the group consisting of:
##STR00043##
[0102] In certain embodiments, each R.sup.3, R.sup.4, and R.sup.5
is independently hydrogen or a substituted or unsubstituted, cyclic
or acyclic, branched or unbranched C.sub.1-C.sub.20 alkenyl. In
certain embodiments, each R.sup.3, R.sup.4, and R.sup.5 is
independently selected from the group consisting of:
##STR00044##
[0103] In certain embodiments, each R.sup.3, R.sup.4, and R.sup.5
is independently selected from the group consisting of:
##STR00045##
[0104] In certain embodiments, each R.sup.3, R.sup.4, and R.sup.5
is independently selected from the group consisting of:
##STR00046##
[0105] In certain embodiments all R.sup.3 and R.sup.4 are hydrogen.
In certain embodiments, each
##STR00047##
is selected from the group consisting of:
##STR00048##
[0106] In certain embodiments, the molecular weight ranges between
1,000 and 100,000 Daltons. In certain embodiments, the molecular
weight ranges between 3,000 and 70,000 Daltons. In certain
embodiments, the molecular weight ranges between 5,000 and 40,000
Daltons. In certain embodiments, the molecular weight ranges
between 5,000 and 30,000 Daltons. In certain embodiments, the
molecular weight ranges between 5,000 and 20,000 Daltons. In
certain embodiments, the molecular weight ranges between 10,000 and
20,000 Daltons.
[0107] In certain embodiments, the polymer has at least one
secondary amine functional group in every repeating unit. In
certain embodiments, the polymer has at least one tertiary amine
functional group in every repeating unit. In certain embodiments,
the polymer has at least one quaternary amine functional group in
every repeating unit.
[0108] In certain embodiments, the polymer is linear. In certain
embodiments, the polymer is water-soluble. In certain embodiments,
the polymer is hydrolytically stable. In certain embodiments, the
polymer is not biodegradable. In certain embodiments, less than 25%
of the polymer is degraded after one year in vivo. In certain
embodiments, less than 10% of the polymer is degraded after one
year in vivo. In certain embodiments, less than 5% of the polymer
is degraded after one year in vivo. In certain embodiments, less
than 1% of the polymer is degraded after one year in vivo. In
certain embodiments, less than 25% of the polymer is degraded after
five years in vivo. In certain embodiments, less than 10% of the
polymer is degraded after five years in vivo. In certain
embodiments, less than 5% of the polymer is degraded after five
years in vivo. In certain embodiments, less than 1% of the polymer
is degraded after five years in vivo.
[0109] In some aspects, the poly(beta-amino alcohol) of the present
invention is prepared from an diepoxide selected from the group
consisting of:
##STR00049## ##STR00050## ##STR00051##
each q is, independently, an integer between 0 and 10, inclusive;
and an amine selected from the group consisting of:
##STR00052## ##STR00053## ##STR00054## ##STR00055##
[0110] In certain embodiments, the poly(beta-amino alcohol) is
selected from the group consisting of: A35, B35, A36, B36, D22,
E22, E35, E36, E09, A34, F35, A29, F09, F32, D20, C22, A06, A32,
F22, F06, B09, B33, E08, F26, D16, F05, C24, A33, B11, E25, A05,
B34, B29, A24, B24, B26, F34, F31, F17, F36, A09, C25, B31, A11,
B07, F16, A31, A23, F29, B04, A16, C13, F23, F33, B03, A17, B28,
B14, A08, F27, A27, B27, A30, and B30. In certain embodiments, the
poly(beta-amino alcohol) is B30.
[0111] Some aspects of the invention include a liposome comprising
any one of the poly(beta-amino alcohols) of the invention and an
agent to be delivered, wherein the agent is selected from the group
consisting of a polynucleotide, RNA, a small molecule, a drug, a
peptide, or a gas. In certain embodiments, the liposome ranges in
size from 10 nanometers to 2000 nanometers.
[0112] Some aspects of the invention include any one of the
poly(beta-amino alcohols) of the invention and an agent to be
delivered. Some aspects of the invention include a device coated
with a poly(beta-amino alcohols) of the invention. Some aspects of
the invention include an implant coated with a poly(beta-amino
alcohols) of the invention. Some aspects of the invention include a
surface coated with a poly(beta-amino alcohols) of the invention.
Some aspects of the invention include a micelle coated with a
poly(beta-amino alcohols) of the invention. Some aspects of the
invention include a complex comprising a poly(beta-amino alcohols)
of the invention and a polynucleotide. Some aspects of the
invention include a method of administering an agent, the method
comprising step of administering to a subject in need thereof a
therapeutically effective amount of a pharmaceutical composition
comprising a poly(beta-amino alcohols) of the invention; and an
agent to be delivered.
[0113] Some aspects of the invention include a method of
encapsulating an agent in a matrix of a poly(beta-amino alcohols)
of the invention to form microparticles, the method comprising
steps of:
[0114] providing an agent;
[0115] providing a poly(beta-amino alcohols) of the invention;
and
[0116] contacting the agent and the polymer under suitable
conditions to form microparticles.
[0117] In certain embodiments, the microparticles inhibit an immune
response. In certain embodiments, the microparticles inhibit
monocyte and/or macrophage activation. In certain embodiments, the
microparticles regulate a foreign body response. In certain
embodiments, the microparticles regulate a cell-material
interaction. In certain embodiments, the microparticles inhibit the
biosynthesis of TNF-.alpha.. In certain embodiments, the
microparticles deliver a nucleic acid. In certain embodiments, the
nucleic acid is DNA. In certain embodiments, the nucleic acid is
siRNA. In certain embodiments, the microparticles modify a
cell-material interaction. In certain embodiments, the
microparticles modify protein adhesion. In certain embodiments, the
microparticles modify cell adhesion. In certain embodiments, the
microparticles modify proliferation, differentiation, or
proliferation and differentiation. In certain embodiments, the
microparticles modify coagulation.
[0118] Some aspects of the invention include a method of coating a
substrate with a polymer of any one of claims 1-3x, the method
comprising steps of:
[0119] providing an substrate;
[0120] providing a poly(beta-amino alcohols) of the invention;
and
[0121] contacting the substrate and the polymer under suitable
conditions to form a coating.
[0122] In certain embodiments, the coating is antimicrobial. In
certain embodiments, the coating is a layer-by-layer (LBL) coating.
In certain embodiments, the coating is a thin film. In certain
embodiments, the coating is a superstructure. In certain
embodiments, the coating is a polyelectrolyte complex capsule. In
certain embodiments, the polyelectrolyte complex capsule is
semi-permeable. In certain embodiments, the coating is an
antifoulant.
Synthesis of Poly(Beta-Amino Alcohols)
[0123] Poly(beta-amino alcohols) may be prepared by any method
known in the art. The polymers may be made, for example, by a
step-growth polymerization of a diepoxide and a bis-secondary amine
or a primary amine. Also, two different diepoxide compounds and/or
two different amine components may be used in the reaction mixture
to prepare the poly(beta-amino alcohol). The epoxide-amine reaction
is generally very robust and efficient even at room temperature.
Similar step growth polymerizations were used to make epoxy-based
thermoplastics (J. E. White, H. C. Silvis, M. S. Winkler, T. W.
Glass, D. E. Kirkpatrick, Adv. Mater. 2000, 12, 1791; J. E. White,
J. Earls, J. W. Sherman, L. C. Lopez, M. L. Dettloff, Polymer 2007,
48, 3990; both incorporated herein by reference) and
copoly(carbosiloxanes) (M. A. Grunlan, N. S. Lee, W. P. Weber,
Polymer 2004, 45, 2517; incorporated herein by reference.)
[0124] Some aspects of the invention include a method of preparing
a poly(beta-amino alcohol); the method comprising the step of
reacting an amine of the formula:
##STR00056##
with a diepoxide of the formula:
##STR00057##
to form a polymer of formula:
##STR00058##
wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, A, B, n, E,
and G are as defined herein.
[0125] In certain embodiments, the poly(beta-amino alcohol) is made
by step-growth polymerization. In certain embodiments, the step of
reacting is performed in the absence of solvent. In certain
embodiments, the step of reacting is performed in the presence of
an aprotic solvent. In certain embodiments, the solvent is
tetrahydrofuran, diethyl ether, ethyl acetate, DMSO, DMF, methanol,
ethanol, or water. In certain embodiments, the reacting step is
performed between about 25.degree. C. and about 50.degree. C. In
certain embodiments, the method of preparing a poly(beta-amino
alcohol) further comprises the step of purifying the product.
[0126] Some aspects of the invention include a method of preparing
a poly(beta-amino alcohol); the method comprising the step of
reacting one or more equivalents of an amine of the formula:
##STR00059##
with a diepoxide of the formula:
##STR00060##
to form a polymer of the formula:
##STR00061##
wherein R.sup.2, R.sup.3, R.sup.4, R.sup.5, B, n, E, and G are as
defined herein.
[0127] In certain embodiments, the poly(beta-amino alcohol) is made
by a step-growth polymerization. In certain embodiments, the step
of reacting is performed in the presence of an aprotic solvent. In
certain embodiments, the solvent is tetrahydrofuran, diethyl ether,
ethyl acetate, DMSO, DMF, methanol, ethanol or water. In certain
embodiments, the reacting step is performed between 25.degree. C.
and 50.degree. C. In certain embodiments, the method of preparing a
poly(beta-amino alcohol) further comprises the step of purifying
the product.
[0128] The polymers were made by a step-growth polymerization of a
diepoxide and a bis-secondary amine or a primary amine. The
epoxide-amine reaction is generally very robust and efficient even
at room temperature. Similar step growth polymerizations were used
to make epoxy-based thermoplastics (J. E. White, H. C. Silvis, M.
S. Winkler, t. W. Glass, D. E. Kirkpatrick, Adv. Mater. 2000, 12,
1791; J. E. While, J. Earls, J. W. Sherman, L. C. Lopez, M. L.
Dettloff, Polymer 2007, 48, 3990) and copoly(carbosiloxanes) (M. A.
Grunlan, N. S. Lee, W. P. Weber, Polymer 2004, 45, 2517). The
general structures of the monomers and polymers are shown below in
the General Scheme. These polymers have several advantages as
potential coatings to regulate the foreign body responses as well
as cell-material interactions in general. First, they are
hydrolytically stable and hydrophilic due to the abundant hydroxyl
groups. Hydrophilicity has been recognized as an important
characteristic of biomaterials with low protein adsorption or cell
adhesion (E. Ostuni, R. G. Chapman, R. E. Holmlin, S. Takayama, G.
M. Whitesides, Langmuir 2001, 17. 5605; N. A. Peppas, J. Z. Hilt,
A. Khademhosseini, R. Langer, Adv. Mater. 2006, 18, 1345). The
non-biofouling properties of oligo(ethylene glycol)-terminated
self-assembled monolayers (SAMs) (P. Harder, M. Grunze, R. Dahint,
G. M. Whitesides, P. E. Laibinis, J. Phys. Chem. B 1998, 102, 426),
zwitterionic SAMs (R. E. Holmlin, X. Chen, R. G. Chapman, S.
Takayama, G. M. Whitesides, Langmuir 2001, 17, 2841) and polymers
(S. Jiang, Z. Cao, Adv. Mater. 2010, 22, 920) have been mainly
attributed to their surface hydration. Second, their synthesis is
relatively simple and no solvent, high temperature, catalyst or
additional chemicals are required. Because of their
water-solubility and cationic nature, the polymers can be easily
immobilized onto a wide range of negatively charged surfaces under
biologically-friendly conditions through electrostatic
interactions. The mild coating conditions are particularly useful
for coating medical devices that are sensitive to heat, UV light,
or organic solvents. Lastly, the availability of a large number of
monomers allows one to screen extremely diverse surface chemistries
for different biological applications.
[0129] Depending on the specific structures of the monomers and
reaction conditions, the typical weight averaged molecular weights
(MW) of the polymers ranged from 7,000 Dalton to 25,000 Dalton with
polydispersity (PDI) of 1.5 to 2.5. The .sup.1H NMR spectra of
selected polymers exhibited clear peak broadening, typical of
polymers. Two common chemical shift (ppm) ranges were around
.delta. 2.2-.delta. 2.8 (characteristic range of H connected to
.alpha. C next to N) and .delta. 3.2-.delta. 3.8 (characteristic
range of H connected to .alpha. C next to --OH). The polymers were
generally soluble in water or slightly acidic solutions with pH
around 4 to 6. The polymers that were insoluble or formed hydrogels
in water were eliminated for further study. In some embodiments,
provided herein are the chemical structures of the 6 epoxides and
36 amines that were chosen to make the polymers. 176 of these
polymers were used for subsequent in vitro screening.
[0130] The polymers were made by a step-growth polymerization of a
diepoxide and a bis-secondary amine or a primary amine. The
epoxide-amine reaction is generally very robust and efficient even
at room temperature. Similar step growth polymerizations were used
to make epoxy-based thermoplastics (J. E. White, H. C. Silvis, M.
S. Winkler, T. W. Glass, D. E. Kirkpatrick, Adv. Mater. 2000, 12,
1791; J. E. White, J. Earls, J. W. Sherman, L. C. Lopez, M. L.
Dettloff, Polymer 2007, 48, 3990) and copoly(carbosiloxanes)(M. A.
Grunlan, N. S. Lee, W. P. Weber, Polymer 2004, 45, 2517). The
general structures of the monomers and polymers are shown below in
the General Scheme. These polymers have several advantages as
potential coatings to regulate the foreign body responses as well
as cell-material interactions in general. First, they are
hydrolytically stable and hydrophilic due to the abundant hydroxyl
groups. Hydrophilicity has been recognized as an important
characteristic of biomaterials with low protein adsorption or cell
adhesion (E. Ostuni, R. G. Chapman, R. E. Holmlin, S. Takayama, G.
M. Whitesides, Langmuir 2001, 17. 5605; N. A. Peppas, J. Z. Hilt,
A. Khademhosseini, R. Langer, Adv. Mater. 2006, 18, 1345). The
non-biofouling properties of oligo(ethylene glycol)-terminated
self-assembled monolayers (SAMs) (P. Harder, M. Grunze, R. Dahint,
G. M. Whitesides, P. E. Laibinis, J. Phys. Chem. B 1998, 102, 426),
zwitterionic SAMs (R. E. Holmlin, X. Chen, R. G. Chapman, S.
Takayama, G. M. Whitesides, Langmuir 2001, 17, 2841) and polymers
(S. Jiang, Z. Cao, Adv. Mater. 2010, 22, 920) have been mainly
attributed to their surface hydration. Second, their synthesis is
relatively simple and no solvent, high temperature, catalyst or
additional chemicals are required. Because of their
water-solubility and cationic nature, the polymers can be easily
immobilized onto a wide range of negatively charged surfaces under
biologically-friendly conditions through electrostatic
interactions. The mild coating conditions are particularly useful
for coating medical devices that are sensitive to heat, UV light,
or organic solvents. Lastly, the availability of a large number of
monomers allows one to screen extremely diverse surface chemistries
for different biological applications.
[0131] A large number of chemically diverse polymers can be
obtained through the variation of substituents R.sup.1, R.sup.2,
R.sup.3, R.sup.4, R.sup.5, A, B, E, and G as shown below. Depending
on the specific structures of the monomers and reaction conditions,
the typical weight averaged molecular weights (MW) of the polymers
ranged from 7,000 Dalton to 25,000 Dalton with polydispersity (PDI)
of 1.5 to 2.5. The .sup.1H NMR spectra of selected polymers
exhibited clear peak broadening, typical of polymers. Two common
chemical shift (ppm) ranges were around .delta. 2.2-.delta. 2.8
(characteristic range of H connected to a C next to N) and .delta.
3.2-.delta. 3.8 (characteristic range of H connected to a C next to
--OH). The polymers were generally soluble in water or slightly
acidic solutions with pH around 4 to 6. The polymers that were
insoluble or formed hydrogels in water were eliminated for further
study. The chemical structures of exemplary epoxides (e.g.,
expoxides A to T) and amines (e.g., amines 1 to 36) chosen to make
polymers of the present invention are shown below. 176 of these
polymers were used for subsequent in vitro screening (see the
Examples, below).
##STR00062##
Exemplary Epoxide Monomers Used to Make PBAAS
##STR00063## ##STR00064##
[0132] wherein each q is, independently, an integer between 0 and
10, inclusive.
Exemplary Amine Monomers Used to Make PBAAS
##STR00065## ##STR00066## ##STR00067##
[0134] Preferably the poly(beta-amino alcohols) are prepared from
commercially available starting materials, such as diepoxides and
amines. In another embodiment, the poly(beta-amino alcohols) are
prepared from easily and/or inexpensively prepared starting
materials. As would be appreciated by one of skill in the art, the
inventive poly(beta-amino alcohols) can be prepared by total
synthesis starting from commercially available starting materials.
A particular poly(beta-amino alcohols) may be the desired final
product of the synthesis, or a mixture of poly(beta-amino alcohols)
may be the desired final product.
[0135] Any amine containing between one, two, three, four, and five
amine functionalities is useful in preparing inventive
poly(beta-amino alcohols). Primary amines useful in this invention
include, but are not limited to, methylamine, ethylamine,
isopropylamine, aniline, substituted anilines, ethanolamine,
decylamine, undecylamine, dodecylamine, tetradecylamine,
hexadecylamine, and octadecylamine. The amine may be a bis(primary
amine) including, but not limited to, ethylenediamine, 1,3
diaminopropane, 1,4 diamino butane, 1,5 diaminopentane, 1,6
diaminohexane, and 2,2'(ethylenedioxy)bis(ethylamine). The amine
may be a bis(secondary amine). Secondary amines useful in this
invention include, but are not limited to, dipropylamine and
methylpentylamine. The amine may include both primary and secondary
amines including, but not limited to, (2-aminoethyl) ethanolamine,
diethylenetriamine, and triethylenetetramine. Preferably, the amine
is commercially available. In certain embodiments, the amine is
stereochemically pure (e.g., enantiomerically pure).
[0136] Diepoxides that are useful in the present invention include
racemic compounds or stereoisomers thereof, all of varying chain
lengths and feature unique functional groups having varying degrees
of saturation. In certain embodiments, the diepoxide is
stereochemically pure (e.g., enantiomerically pure). In certain
embodiments, the diepoxide contains one or more chiral centers. In
certain embodiments, the epoxides are of the formula A through 0 as
shown above.
[0137] The chiral epoxides useful in the invention can be obtained
from a variety of sources which are familiar to those skilled in
the art of organic synthesis. In some embodiments, the chiral
epoxides useful in the invention can be obtained commercially. In
some embodiments, the chiral epoxides useful in the invention can
be synthesized according to methods known to those of skill in the
art, such as, but not limited to the Sharpless epoxidation of
primary and secondary allylic alcohols into 2,3-epoxyalcohols
(Katsuki et al., J. Am. Chem. Soc. 1980, 102, 5974; Hill et al.,
Org. Syn., Coll. Vol. 7, p. 461 (1990); Vol. 63, p. 66 (1985);
Katsuki et al., Org. React. 1996, 48, 1-300; incorporated herein by
reference.) In some embodiments, the chiral epoxides useful in the
invention are obtained from the resolution of racemic epoxides. In
some embodiments, the chiral epoxides useful in the invention are
obtained by the separation of enantiomers or diastereoisomers using
chiral chromatography.
[0138] In certain embodiments, the reaction is performed neat
without the use of a solvent. In other embodiments, a solvent is
used for the reaction. Both or one of the starting amine or
epoxide-terminated compound is dissolved in an organic solvent
(e.g., THF, CH.sub.2Cl.sub.2, MeOH, EtOH, CHCl.sub.3, hexanes,
toluene, benzene, CCl.sub.4, glyme, diethyl ether, etc.). The
resulting solutions are combined, and the reaction mixture is
heated to yield the desired poly(beta-amino alcohol). In certain
embodiments, the reaction mixture is heated to a temperature
ranging from approx. 25.degree. C. to approx. 100.degree. C.,
preferably at approximately 90.degree. C. The reaction may also be
catalyzed. For example, the reaction may be catalyzed by the
addition of an acid, base, or metal. The reagents may be allowed to
react for hours, days, or weeks. Preferably, the reaction is
allowed to proceed from overnight (e.g., 8-12 hours) to 7 days.
[0139] The synthesized poly(beta-amino alcohol) may be purified by
any technique known in the art including, but not limited to,
precipitation, crystallization, chromatography, distillation, etc.
In certain embodiments, the poly(beta-amino alcohol) is purified
through repeated precipitations in organic solvent (e.g., diethyl
ether, hexane, etc.). In certain embodiments, the poly(beta-amino
alcohol) polymer is isolated as a salt. The poly(beta-amino
alcohol) is reacted with an acid (e.g., an organic acid or
inorganic acid) to form the corresponding salt. In certain
embodiments, the tertiary amine is alkylated to form a quaternary
ammonium salt of the poly(beta-amino alcohol). The tertiary amines
may be alkylated with any alkylating agent, for example, alkyl
halides such as methyl iodide may be used to from the quaternary
amino groups. The anion associated with the quaternary amine may be
any organic or inorganic anion. Preferably, the anion is a
pharmaceutically acceptable anion.
[0140] In certain embodiments, the reaction mixture results in a
mixture of isomers. Such mixtures of products or compounds may be
used as is, or a single isomer, or compound, may be purified from
the reaction mixture. When an amine is not exhaustively alkylated,
the resulting primary, secondary, or tertiary amines may be further
reacted with another poly(beta-amino alcohol), diepoxide, epoxide,
or other electrophile. The resulting poly(beta-amino alcohol) may
then be optionally purified.
[0141] In certain embodiments, a desired poly(beta-amino alcohol)
is prepared by traditional total synthesis. In certain embodiments,
a commercially available amine is the starting material. One or
more amino groups of the amine are optionally protected. The
unprotected amino groups are reacted with an epoxide-terminated
compound. The product is optionally purified. Protecting groups are
removed, and the free amino groups are optionally reacted with
another poly(beta-amino alcohol), diepoxide, epoxide, or other
electrophile. Such a sequence may be repeated depending on the
desired complexity of the inventive product being prepared. The
final product may then be optionally purified.
[0142] In one embodiment, a library of different poly(beta-amino
alcohols) is prepared in parallel. A different amine and/or
diepoxide is added to each vial in a set of vials or to each well
of a multi-well plate used to prepare the library. The array of
reaction mixtures is incubated at a temperature and length of time
sufficient to allow formation of the poly(beta-amino alcohol) to
occur. In one embodiment, the vials are incubated at approximately
90.degree. C. overnight. In certain embodiments, the vials are
incubated from 1 to 7 days at approximately 90.degree. C. In
certain embodiments, the vials are incubated from 3 to 4 days at
approximately 90.degree. C. In certain embodiments, the vials are
incubated from 1 to 2 days at approximately 90.degree. C. The
poly(beta-amino alcohol) may then be isolated and purified using
techniques known in the art. The poly(beta-amino alcohol) may then
be screened using high-throughput techniques to identify
poly(beta-amino alcohols) with a desired characteristic (e.g.,
solubility in water, solubility at different pH, ability to bind
polynucleotides, ability to bind heparin, ability to bind small
molecules, ability to bind protein, ability to form microparticles,
ability to increase tranfection efficiency, etc.). In certain
embodiments the poly(beta-amino alcohols) may be screened for
properties or characteristics useful as coatings, additives,
materials, and excipients in biotechnology and biomedical
applications such as the coating of medical devices or implants
with films or multilayer films, as non-biofouling agents,
micropatterning agents, and cellular encapsulation agents. In
certain embodiments the poly(beta-amino alcohols) may be screened
for properties or characteristics useful in gene therapy (e.g.,
ability to bind polynucleotides, increase in transfection
efficiency) or the administration and/or delivery of therapeutic
agents (e.g., polynucleotide, small molecule, antigen, drug,
protein, peptide, etc.) to a subject, patient, tissue, organ, or
cell, etc.
Poly(Beta-Amino Alcohols) as Coatings
[0143] The inventive poly(beta-amino alcohols) have several
advantages as potential coatings to regulate the foreign body
responses as well as cell-material interactions in general. First,
they are hydrolytically stable and exceptionally hydrophilic due to
the abundant hydroxyl groups. The hydrophilicity has been
recognized as an important factor in developing biomaterials with
low protein adsorption or cell adhesion (E. Ostuni, R. G. Chapman,
R. E. Holmlin, S. Takayama, G. M. Whitesides, Langmuir 2001, 17.
5605; N. A. Peppas, J. Z. Hilt, A. Khademhosseini, R. Langer, Adv.
Mater. 2006, 18, 1345; incorporated herein by reference.) The
non-biofouling properties of oligo(ethylene glycol)-terminated
self-assembled monolayers (SAMs) (P. Harder, M. Grunze, R. Dahint,
G. M. Whitesides, P. E. Laibinis, J. Phys. Chem. B 1998, 102, 426;
incorporated herein by reference,) zwitterionic SAMs (R. E.
Holmlin, X. Chen, R. G. Chapman, S. Takayama, G. M. Whitesides,
Langmuir 2001, 17, 2841; incorporated herein by reference) and
polymers (S. Jiang, Z. Cao, Adv. Mater. 2010, 22, 920; incorporated
herein by reference) were mainly attributed to the surface
hydration. Second, their water-solubility and cationic nature make
it relatively simple to coat a wide range of surfaces under
biologically-friendly conditions using electrostatic interactions.
The mild coating conditions are useful for coatings on medical
devices that are sensitive to heat, UV light, or organic solvents.
Lastly, the simplicity of their synthesis without requirements of
solvent, high temperature, catalyst or additional chemicals, and
the availability of a large number of monomers allow one to screen
extremely diverse surface chemistries for different biological
applications.
[0144] Among the different techniques used to modify surfaces, the
deposition of polyelectrolyte multilayers (PEM) has emerged as a
very easy handling and versatile tool. Based on the alternate
adsorption of polycations and polyanions, this technique allows to
buildup films with tunable properties: by adjusting several
parameters such as the chemical nature of the polyelectrolytes, pH
and ionic strength, immersion and rinsing times, post-treatment of
the film, it is possible to obtain an almost infinite variety of
architectures. The introduction of electrostatic layer-by-layer
(LBL) self-assembly also called electrostatic self-assembly (ESA)
has shown broad biotechnology and biomedical applications in thin
film coating, micropatterning, nanobioreactors, artificial cells,
integrated optics, microelectronic devices, sensors, optical memory
devices, encapsulation and drug delivery systems. Indeed, this kind
of film is easy to manufacture.
[0145] Of special importance for biomedical applications is the
control of the chemical composition of the surface which can affect
biocompatibility or biological activity. Films made from
poly(beta-amino alcohols) allow, for example, biomimetic
architectures to be created. Applications include also the
fabrication of non-adhesive barriers for vascular grafts, the
fabrication of films with pro- or anti-coagulant properties or the
preparation of hollow capsules for drug release. Bioactivity, such
as antimicrobial activity or antifibrosis activity, of the films
can be achieved by their functionalization by with amines and
diepoxides. For biomaterial applications, biocompatibility is a
major requirement: the material or the film covering a material
surface must be non-cytotoxic to any living cell and not iatrogenic
or allergenic. Another requirement is that the material possesses
chemical and physical properties that promote specific cell
interactions, either cell adhesion or non-adhesion depending on the
final application.
[0146] The poly(beta-amino alcohols) of the present invention are
biostable. For various applications, the preservation of the
structural integrity of the film is crucial. For a long term use of
these films (e.g. days, weeks, or months) in aggressive conditions
(pH, ionic strength, solvents), it is important that the stability
(in particular biostability) of the films is maintained. This
property is particularly of interest for films designed to be in
contact with a tissue or fluid within the body (soft tissue, blood,
lymph, etc.) which contains different types of proteins (for
example enzymes), cells and phagocytic cells (for example, white
blood cells).
[0147] It therefore is an object of this invention to provide a
method for producing biostable polyelectrolyte multilayers films
made from poly(beta-amino alcohols). It is a further object of the
invention to provide a method of producing certain biocompatible
materials made from poly(beta-amino alcohols), such materials
representing, for example, a surface coated with poly(beta-amino
alcohols). Furthermore, it is an object of the invention to provide
multilayers films made from poly(beta-amino alcohols) wherein
various cells types can adhere and proliferate.
Treatment of Medical Devices and Implants with Poly(Beta-Amino
Alcohols)
[0148] An aspect of the invention includes the treatment of medical
devices and implants with poly(beta-amino alcohols) such treatment
may inhibit infection or microorganism growth or colonization.
Infections associated with medical implants represent a major
healthcare problem. A significant percentage of these infections
are related to bacterial colonization of implanted medical implants
such as Foley catheters (urinary tract infections), surgical
drains, meshes, sutures, artificial joints, vascular grafts (wound
infections); endotracheal and tracheostomy tubes (respiratory tract
infection); and vascular infusion catheters (bloodstream
infections). Although any infectious agent can infect medical
implant, Staphylococci (S. aureus, S. epidermidis, S. pyogenes),
Enterococci (E. coli), Gram negative aerobic Bacilli, and
Pseudomonas aeruginosa are common causes. Once a medical implant
becomes colonized by bacteria, it must frequently be replaced
resulting in increased morbidity for the patient and increased cost
to the healthcare system. Often the infected device serves as a
source for a disseminated infection which can lead to significant
morbidity or even death. Thus, there is a need in the art for
medical implants which have a reduced likelihood of an associated
infection. Treatment of medical devices and implants with
poly(beta-amino alcohols) may reduce the likelihood of infections
in medical implants, and further, provides other, related
advantages.
[0149] A further aspect of the invention includes the treatment of
medical devices and implants with poly(beta-amino alcohols) to
inhibit fibrosis. "Fibrosis," "scarring," or "fibrotic response"
refers to the formation of fibrous tissue in response to injury or
medical intervention. Polymers which inhibit fibrosis or scarring
are referred to herein as "fibrosis-inhibiting polymers,"
"anti-scarring polymers," and the like, where these polymers
inhibit fibrosis through one or more mechanisms including, but not
limited to, inhibiting angiogenesis, inhibiting migration or
proliferation of connective tissue cells (such as fibroblasts,
smooth muscle cells, vascular smooth muscle cells), reducing ECM
production, and/or inhibiting tissue remodeling.
[0150] The clinical function of numerous medical implants and
devices is dependent upon the device being able to effectively
maintain an anatomical, or surgically created, space or passageway.
Unfortunately, many devices implanted in the body are subject to a
"foreign body" response from the surrounding host tissues. In
particular, injury to tubular anatomical structures (such as blood
vessels, the gastrointestinal tract, the male and female
reproductive tract, the urinary tract, sinuses, spinal nerve root
canals, lacrimal ducts, Eustachian tubes, the auditory canal, and
the respiratory tract) from surgery and/or injury created by the
implantation of medical devices can lead to a well known clinical
problem called "stenosis" (or narrowing). Stenosis occurs in
response to trauma to the epithelial lining or the entire body tube
during the procedure, including virtually any manipulation which
attempts to relieve obstruction of the passageway, and is a major
factor limiting the effectiveness of invasive treatments for a
variety of diseases to be described later.
[0151] Stenosis (or "restenosis" if the problem recurs after an
initially successful attempt to open a blocked passageway) is a
form of response to injury leading to wall thickening, narrowing of
the lumen, and loss of function in the tissue supplied by the
particular passageway. Physical injury during an interventional
procedure results in damage to epithelial lining of the tube and
the smooth muscle cells (SMCs) that make up the wall. The damaged
cells, particularly SMCs, release cytokines, which recruit
inflammatory cells such as macrophages, lymphocytes and neutrophils
(i.e., which are some of the known white blood cells) into the
area. The white blood cells in turn release a variety of additional
cytokines, growth factors, and tissue degrading enzymes that
influence the behavior of the constituent cells of the wall
(primarily epithelial cells and SMCs). Stimulation of the SMCs
induces them to migrate into the inner aspect of the body
passageway (often called the "intima"), proliferate and secrete an
extracellar matrix--effectively filling all or parts of the lumen
with reactive, fibrous scar tissue. Collectively, this creates a
thickening of the intimal layer (known in some tissues as
"neointimal hyperplasia") that narrows the lumen of the passageway
and can be significant enough to obstruct its lumen.
[0152] The present invention discloses poly(beta-amino alcohols)
which inhibit one or more aspects of the production of excessive
fibrous (scar) tissue. Furthermore, compositions and methods are
described for coating medical devices and implants with
poly(beta-amino alcohol) polymers to allow normal healing to
occur.
[0153] Also provided by the present invention are methods for
treating patients undergoing surgical, endoscopic or minimally
invasive therapies where a medical device or implant, coated with
poly(beta-amino alcohols), is placed as part of the procedure. As
utilized herein, it should be understood that "inhibits fibrosis or
stenosis" refers to a statistically significant decrease in the
amount of scar tissue in or around the device or an improvement in
the luminal area of the device/implant, which may or may not result
in a permanent prohibition of any complications or failures of the
device/implant.
[0154] Implants and medical devices treated with poly(beta-amino
alcohols) may reduce the foreign body response to implantation and
limit the growth of reactive tissue on the surface of, or around in
the tissue surrounding the implants and medical devices, such that
performance is enhanced. In many instances, the devices are used to
maintain body lumens or passageways such as blood vessels, the
gastrointestinal tract, the male and female reproductive tract, the
urinary tract, bony foramena (e.g., sinuses, spinal nerve root
canals, lacrimal ducts, Eustachian tubes, the auditory canal), and
the respiratory tract, where obstruction of the device by scar
tissue in the post-procedural period leads to the adverse clinical
sequela or failure of the intervention. Medical devices and
implants coated with the inventive poly(beta-amino alcohols) which
prevent scar tissue overgrowth and preserve patency can offer
significant clinical advantages over uncoated devices.
[0155] Implants and other surgical or medical devices may be
covered, coated, contacted, combined, loaded, filled, associated
with, or otherwise adapted to release the poly(beta-amino alcohols)
of the present invention in a variety of manners, including for
example: (a) by directly affixing to the implant or device a
poly(beta-amino alcohol) or composition (e.g., by either spraying
the implant or device with a poly(beta-amino alcohol) film, or by
dipping the implant or device into a poly(beta-amino alcohol)
solution, or by other covalent or noncovalent means); (b) by
coating the implant or device with a substance, such as a hydrogel,
which will in turn absorb the poly(beta-amino alcohol) composition
(or therapeutic factor above); (c) by interweaving poly(beta-amino
alcohol) coated thread (or the poly(beta-amino alcohol) itself
formed into a thread) into the implant or device; (d) by inserting
the implant or device into a sleeve or mesh which is comprised of
or coated with a poly(beta-amino alcohol); (e) constructing the
implant or device itself with a poly(beta-amino alcohol); or (f) by
otherwise adapting the implant or device to release the
poly(beta-amino alcohol). Within preferred embodiments of the
invention, the composition should firmly adhere to the implant or
device during storage and at the time of insertion. The
poly(beta-amino alcohol) or composition should also preferably not
degrade during storage, prior to insertion, or when warmed to body
temperature after insertion inside the body (if this is required).
In addition, it should preferably coat or cover the desired areas
of the implant or device smoothly and evenly, with a uniform
distribution of poly(beta-amino alcohol). Within some preferred
embodiments of the invention, the poly(beta-amino alcohol) or
composition should provide a uniform, predictable, prolonged
release of the poly(beta-amino alcohol) into the tissue surrounding
the implant or device once it has been deployed. Within other
preferred embodiments of the invention, the poly(beta-amino
alcohol) or composition should resist a prolonged release of the
poly(beta-amino alcohol) into the tissue surrounding the implant or
device once it has been deployed. For vascular stents, in addition
to the above properties, the composition should not render the
stent thrombogenic (causing blood clots to form), or cause
significant turbulence in blood flow (more than the stent itself
would be expected to cause if it was uncoated).
[0156] Within certain embodiments of the invention, the
poly(beta-amino alcohol) can be deposited directly onto all or a
portion of the device (see, e.g., U.S. Pat. Nos. 6,096,070 and
6,299,604; both incorporated herein by reference) or admixed with a
delivery system or carrier (e.g., a polymer, liposome, or
additional agent as discussed above) which is applied to all or a
portion of the device.
[0157] To further modulate or prevent the release of the
poly(beta-amino alcohol) from the medical implant, portions of or
the entire medical implant may be further coated with additional
agents or polymers to increase the flexibility (e.g.,
plasticizer-glycerol, triethyl citrate), lubricity (e.g.,
hyaluronic acid), biocompatibility, bioactivity, or
hemocompatability (e.g., heparin) of the coating.
Polynucleotide Complexes
[0158] The ability of cationic compounds to interact with
negatively charged polynucleotides through electrostatic
interactions is well known. Cationic lipids such as Lipofectamine
have been prepared and studied for their ability to complex and
transfect polynucleotides. The interaction of the lipid with the
polynucleotide is thought to at least partially prevent the
degradation of the polynucleotide. By neutralizing the charge on
the backbone of the polynucleotide, the neutral or
slightly-positively-charged complex is also able to more easily
pass through the hydrophobic membranes (e.g., cytoplasmic,
lysosomal, endosomal, nuclear) of the cell. In certain embodiments,
the complex is slightly positively charged. In certain embodiments,
the complex has a positive .zeta.-potential, more preferably the
.zeta.-potential is between 0 and +30.
[0159] The poly(beta-amino alcohols) of the present invention
possess tertiary amines. Although these amines are hindered, they
are available to interact with a polynucleotide (e.g., DNA, RNA,
synthetic analogs of DNA and/or RNA, DNA/RNA hydrids, etc.).
Polynucleotides or derivatives thereof are contacted with the
inventive poly(beta-amino alcohols) under conditions suitable to
form polynucleotide/poly(beta-amino alcohol). The polymer is
preferably at least partially protonated so as to form a complex
with the negatively charged polynucleotide. In certain embodiments,
the polynucleotide/poly(beta-amino alcohol) complexes form
particles that are useful in the delivery of polynucleotides to
cells. In certain embodiments, multiple poly(beta-amino alcohols)
may be associated with a polynucleotide molecule. The complex may
include 1-100 poly(beta-amino alcohols), 1-1000 poly(beta-amino
alcohols), 10-1000 poly(beta-amino alcohols), or 100-10,000
poly(beta-amino alcohols).
[0160] In certain embodiments, the complex may form a particle. In
certain embodiments, the diameter of the particles ranges from
10-500 micrometers. In certain embodiments, the diameter of the
particles ranges from 10-1200 micrometers. In certain embodiments,
the diameter of the particles ranges from 50-150 micrometers. In
certain embodiments, the diameter of the particles ranges from
10-500 nm, more preferably the diameter of the particles ranges
from 10-1200 nm, and most preferably from 50-150 nm. The particles
may be associated with a targeting agent as described below. In
certain embodiments, the diameter of the particles ranges from
10-500 .mu.m, more preferably the diameter of the particles ranges
from 10-1200 .mu.m, and most preferably from 50-150 .mu.m. The
particles may be associated with a targeting agent as described
below. The film architecture is precisely designed and can be
controlled to 1 nm precision with a range from 1 to 150000 nm and
with a definite knowledge of its molecular composition.
[0161] The polynucleotide to be complexed, encapsulated by the
inventive poly(beta-amino alcohols), or included in a composition
with the inventive poly(beta-amino alcohols) may be any nucleic
acid including, but not limited to, RNA and DNA. In certain
embodiments, the polynucleotide is DNA. In certain embodiments, the
polynucleotide is RNA.
[0162] In certain embodiments, the polynucleotide is an RNA that
carries out RNA interference (RNAi). The phenomenon of RNAi is
discussed in greater detail, for example, in the following
references, each of which is incorporated herein by reference:
Elbashir et al., 2001, Genes Dev., 15:188; Fire et al., 1998,
Nature, 391:806; Tabara et al., 1999, Cell, 99:123; Hammond et al.,
Nature, 2000, 404:293; Zamore et al., 2000, Cell, 101:25;
Chakraborty, 2007, Curr. Drug Targets, 8:469; and Morris and Rossi,
2006, Gene Ther., 13:553. In certain embodiments, the
polynucleotide is a dsRNA (double-stranded RNA). In certain
embodiments, the polynucleotide is an siRNA (short interfering
RNA). In certain embodiments, the polynucleotide is an shRNA (short
hairpin RNA).
[0163] In certain embodiments, the polynucleotide is an miRNA
(micro RNA). micro RNAs (miRNAs) are genomically encoded non-coding
RNAs of about 21-23 nucleotides in length that help regulate gene
expression, particularly during development (see, e.g., Bartel,
2004, Cell, 116:281; Novina and Sharp, 2004, Nature, 430:161; and
U.S. Patent Publication 2005/0059005; also reviewed in Wang and Li,
2007, Front. Biosci., 12:3975; and Zhao, 2007, Trends Biochem.
Sci., 32:189; each of which are incorporated herein by
reference).
[0164] In certain embodiments, the polynucleotide is an antisense
RNA.
[0165] In some embodiments, a dsRNA, siRNA, shRNA, miRNA and/or
antisense RNA can be designed and/or predicted using one or more of
a large number of available algorithms. To give but a few examples,
the following resources can be utilized to design and/or predict
dsRNA, siRNA, shRNA, and/or miRNA: algorithms found at Alnylum
Online, Dharmacon Online, OligoEngine Online, Molecula Online,
Ambion Online, BioPredsi Online, RNAi Web Online, Chang Bioscience
Online, Invitrogen Online, LentiWeb Online GenScript Online,
Protocol Online; Reynolds et al., 2004, Nat. Biotechnol., 22:326;
Naito et al., 2006, Nucleic Acids Res., 34:W448; Li et al., 2007,
RNA, 13:1765; Yiu et al., 2005, Bioinformatics, 21:144; and Jia et
al., 2006, BMC Bioinformatics, 7: 271; each of which is
incorporated herein by reference).
[0166] The polynucleotides may be of any size or sequence, and they
may be single- or double-stranded. In certain embodiments, the
polynucleotide is greater than 100 base pairs long. In certain
embodiments, the polynucleotide is greater than 1000 base pairs
long and may be greater than 10,000 base pairs long. The
polynucleotide is optionally purified and substantially pure.
Preferably, the polynucleotide is greater than 50% pure, more
preferably greater than 75% pure, and most preferably greater than
95% pure. The polynucleotide may be provided by any means known in
the art. In certain embodiments, the polynucleotide has been
engineered using recombinant techniques (for a more detailed
description of these techniques, please see Ausubel et al., Current
Protocols in Molecular Biology (John Wiley & Sons, Inc., New
York, 1999); Molecular Cloning: A Laboratory Manual, 2nd Ed., ed.
by Sambrook, Fritsch, and Maniatis (Cold Spring Harbor Laboratory
Press: 1989); each of which is incorporated herein by reference).
The polynucleotide may also be obtained from natural sources and
purified from contaminating components found normally in nature.
The polynucleotide may also be chemically synthesized in a
laboratory. In certain embodiments, the polynucleotide is
synthesized using standard solid phase chemistry.
[0167] The polynucleotide may be modified by chemical or biological
means. In certain embodiments, these modifications lead to
increased stability of the polynucleotide. Modifications include
methylation, phosphorylation, end-capping, etc.
[0168] Derivatives of polynucleotides may also be used in the
present invention. These derivatives include modifications in the
bases, sugars, and/or phosphate linkages of the polynucleotide.
Modified bases include, but are not limited to, those found in the
following nucleoside analogs: 2-aminoadenosine, 2-thiothymidine,
inosine, pyrrolo-pyrimidine, 3-methyl adenosine, 5-methylcytidine,
C5-bromouridine, C5-fluorouridine, C5-iodouridine,
C5-propynyl-uridine, C5-propynyl-cytidine, C5-methylcytidine,
7-deazaadenosine, 7-deazaguanosine, 8-oxoadenosine, 8-oxoguanosine,
O(6)-methylguanine, and 2-thiocytidine. Modified sugars include,
but are not limited to, 2'-fluororibose, ribose, 2'-deoxyribose,
3'-azido-2',3'-dideoxyribose, 2',3'-dideoxyribose, arabinose (the
2'-epimer of ribose), acyclic sugars, and hexoses. The nucleosides
may be strung together by linkages other than the phosphodiester
linkage found in naturally occurring DNA and RNA. Modified linkages
include, but are not limited to, phosphorothioate and
5'-N-phosphoramidite linkages. Combinations of the various
modifications may be used in a single polynucleotide. These
modified polynucleotides may be provided by any means known in the
art; however, as will be appreciated by those of skill in this art,
the modified polynucleotides are preferably prepared using
synthetic chemistry in vitro.
[0169] The polynucleotides to be delivered may be in any form. For
example, the polynucleotide may be a circular plasmid, a linearized
plasmid, a cosmid, a viral genome, a modified viral genome, an
artificial chromosome, etc.
[0170] The polynucleotide may be of any sequence. In certain
embodiments, the polynucleotide encodes a protein or peptide. The
encoded proteins may be enzymes, structural proteins, receptors,
soluble receptors, ion channels, pharmaceutically active proteins,
cytokines, interleukins, antibodies, antibody fragments, antigens,
coagulation factors, albumin, growth factors, hormones, insulin,
etc. The polynucleotide may also comprise regulatory regions to
control the expression of a gene. These regulatory regions may
include, but are not limited to, promoters, enhancer elements,
repressor elements, TATA box, ribosomal binding sites, stop site
for transcription, etc. In certain embodiments, the polynucleotide
is not intended to encode a protein. For example, the
polynucleotide may be used to fix an error in the genome of the
cell being transfected.
[0171] The polynucleotide may also be provided as an antisense
agent or RNA interference (RNAi) (Fire et al., Nature 391:806-811,
1998; incorporated herein by reference). Antisense therapy is meant
to include, e.g., administration or in situ provision of single- or
double-stranded oligonucleotides or their derivatives which
specifically hybridize, e.g., bind, under cellular conditions, with
cellular mRNA and/or genomic DNA, or mutants thereof, so as to
inhibit expression of the encoded protein, e.g., by inhibiting
transcription and/or translation (Crooke "Molecular mechanisms of
action of antisense drugs" Biochim. Biophys. Acta 1489(1):31-44,
1999; Crooke "Evaluating the mechanism of action of
antiproliferative antisense drugs" Antisense Nucleic Acid Drug Dev.
10(2):123-126, discussion 127, 2000; Methods in Enzymology volumes
313-314, 1999; each of which is incorporated herein by reference).
The binding may be by conventional base pair complementarity, or,
for example, in the case of binding to DNA duplexes, through
specific interactions in the major groove of the double helix
(i.e., triple helix formation) (Chan et al., J. Mol. Med.
75(4):267-282, 1997; incorporated herein by reference).
[0172] In certain embodiments, the polynucleotide to be delivered
comprises a sequence encoding an antigenic peptide or protein.
Nanoparticles containing these polynucleotides can be delivered to
an individual to induce an immunologic response sufficient to
decrease the chance of a subsequent infection and/or lessen the
symptoms associated with such an infection. The polynucleotide of
these vaccines may be combined with interleukins, interferon,
cytokines, and adjuvants such as cholera toxin, alum, Freund's
adjuvant, etc. A large number of adjuvant compounds are known; a
useful compendium of many such compounds is prepared by the
National Institutes of Health and can be found on the internet
(www.niaid.nih.gov/daids/vaccine/pdf/compendium.pdf, incorporated
herein by reference; see also Allison Dev. Biol. Stand. 92:3-11,
1998; Unkeless et al., Annu. Rev. Immunol. 6:251-281, 1998; and
Phillips et al., Vaccine 10:151-158, 1992; each of which is
incorporated herein by reference).
[0173] The antigenic protein or peptides encoded by the
polynucleotide may be derived from such bacterial organisms as
Streptococccus pneumoniae, Haemophilus influenzae, Staphylococcus
aureus, Streptococcus pyrogenes, Corynebacterium diphtheriae,
Listeria monocytogenes, Bacillus anthracis, Clostridium tetani,
Clostridium botulinum, Clostridium perfringens, Neisseria
meningitidis, Neisseria gonorrhoeae, Streptococcus mutans,
Pseudomonas aeruginosa, Salmonella typhi, Haemophilus
parainfluenzae, Bordetella pertussis, Francisella tularensis,
Yersinia pestis, Vibrio cholerae, Legionella pneumophila,
Mycobacterium tuberculosis, Mycobacterium leprae, Treponema
pallidum, Leptospirosis interrogans, Borrelia burgdorferi,
Camphylobacter jejuni, and the like; from such viruses as smallpox,
influenza A and B, respiratory syncytial virus, parainfluenza,
measles, HIV, varicella-zoster, herpes simplex 1 and 2,
cytomegalovirus, Epstein-Barr virus, rotavirus, rhinovirus,
adenovirus, papillomavirus, poliovirus, mumps, rabies, rubella,
coxsackieviruses, equine encephalitis, Japanese encephalitis,
yellow fever, Rift Valley fever, hepatitis A, B, C, D, and E virus,
and the like; and from such fungal, protozoan, and parasitic
organisms such as Cryptococcus neoformans, Histoplasma capsulatum,
Candida albicans, Candida tropicalis, Nocardia asteroides,
Rickettsia ricketsii, Rickettsia typhi, Mycoplasma pneumoniae,
Chlamydial psittaci, Chlamydial trachomatis, Plasmodium falciparum,
Trypanosoma brucei, Entamoeba histolytica, Toxoplasma gondii,
Trichomonas vaginalis, Schistosoma mansoni, and the like.
Particles
[0174] The poly(beta-amino alcohols) of the present invention may
also be used to form drug delivery devices. The inventive
poly(beta-amino alcohols) may be used to encapsulate agents
including polynucleotides, small molecules, proteins, peptides,
metals, organometallic compounds, etc. The inventive
poly(beta-amino alcohols) have several properties that make them
particularly suitable in the preparation of drug delivery devices.
These include: 1) the ability of the lipid to complex and "protect"
labile agents; 2) the ability to buffer the pH in the endosome; 3)
the ability to act as a "proton sponge" and cause endosomolysis;
and 4) the ability to neutralize the charge on negatively charged
agents. In certain embodiments, the poly(beta-amino alcohols) are
used to form particles containing the agent to be delivered. These
particles may include other materials such as proteins,
carbohydrates, synthetic polymers (e.g., PEG, PLGA), and natural
polymers.
[0175] In certain embodiments, the diameter of the particles range
from between 1 micrometer to 1,000 micrometers. In certain
embodiments, the diameter of the particles range from between from
1 micrometer to 100 micrometers. In certain embodiments, the
diameter of the particles range from between from 1 micrometer to
10 micrometers. In certain embodiments, the diameter of the
particles range from between from 10 micrometer to 100 micrometers.
In certain embodiments, the diameter of the particles range from
between from 100 micrometer to 1,000 micrometers. In certain
embodiments, the particles range from 1-5 micrometers. In certain
embodiments, the diameter of the particles range from between 1 nm
to 1,000 nm. In certain embodiments, the diameter of the particles
range from between from 1 nm to 100 nm. In certain embodiments, the
diameter of the particles range from between from 1 nm to 10 nm. In
certain embodiments, the diameter of the particles range from
between from 10 nm to 100 nm. In certain embodiments, the diameter
of the particles range from between from 100 nm to 1,000 nm. In
certain embodiments, the particles range from 1-5 nm. In certain
embodiments, the diameter of the particles range from between 1 pm
to 1,000 pm. In certain embodiments, the diameter of the particles
range from between from 1 pm to 100 pm. In certain embodiments, the
diameter of the particles range from between from 1 pm to 10 pm. In
certain embodiments, the diameter of the particles range from
between from 10 pm to 100 pm. In certain embodiments, the diameter
of the particles range from between from 100 pm to 1,000 pm. In
certain embodiments, the particles range from 1-5 pm.
[0176] The inventive particles may be prepared using any method
known in this art. These include, but are not limited to, spray
drying, single and double emulsion solvent evaporation, solvent
extraction, phase separation, simple and complex coacervation, and
other methods well known to those of ordinary skill in the art. In
certain embodiments, methods of preparing the particles are the
double emulsion process and spray drying. The conditions used in
preparing the particles may be altered to yield particles of a
desired size or property (e.g., hydrophobicity, hydrophilicity,
external morphology, "stickiness", shape, etc.). The method of
preparing the particle and the conditions (e.g., solvent,
temperature, concentration, air flow rate, etc.) used may also
depend on the agent being encapsulated and/or the composition of
the matrix.
[0177] Methods developed for making particles for delivery of
encapsulated agents are described in the literature (for example,
please see Doubrow, M., Ed., "Microcapsules and Nanoparticles in
Medicine and Pharmacy," CRC Press, Boca Raton, 1992; Mathiowitz and
Langer, J. Controlled Release 5:13-22, 1987; Mathiowitz et al.,
Reactive Polymers 6:275-283, 1987; Mathiowitz et al., J. Appl.
Polymer Sci. 35:755-774, 1988; each of which is incorporated herein
by reference).
[0178] If the particles prepared by any of the above methods have a
size range outside of the desired range, the particles can be
sized, for example, using a sieve. The particle may also be coated.
In certain embodiments, the particles are coated with a targeting
agent. In other embodiments, the particles are coated to achieve
desirable surface properties (e.g., a particular charge).
Micelles and Liposomes
[0179] The poly(beta-amino alcohols) of the invention may also be
used to prepare micelles or liposomes. Many techniques for
preparing micelles and liposomes are known in the art, and any
method may be used with the inventive poly(beta-amino alcohols) to
make micelles and liposomes. In addition, any agent including
polynucleotides, small molecules, proteins, peptides, metals,
organometallic compounds, etc. may be included in a micelle or
liposome. Micelles and liposomes are particularly useful in
delivering hydrophobic agents such as hydrophobic small
molecules.
[0180] In certain embodiments, liposomes (lipid or poly(beta-amino
alcohol) vesicles) are formed through spontaneous assembly. In
other embodiments, liposomes are formed when thin lipid films or
lipid cakes are hydrated and stacks of lipid crystalline bilayers
become fluid and swell. The hydrated lipid sheets detach during
agitation and self-close to form large, multilamellar vesicles
(LMV). This prevents interaction of water with the hydrocarbon core
of the bilayers at the edges. Once these particles have formed,
reducing the size of the particle can be modified through input of
sonic energy (sonication) or mechanical energy (extrusion). See
Walde, P. "Preparation of Vesicles (Liposomes)" In Encylopedia of
Nanoscience and Nanotechnology; Nalwa, H. S. Ed. American
Scientific Publishers: Los Angeles, 2004; Vol. 9, pp. 43-79; Szoka
et al., "Comparative Properties and Methods of Preparation of Lipid
Vesicles (Liposomes)" Ann. Rev. Biophys. Bioeng. 9:467-508, 1980;
each of which is incorporated herein. The preparation of lipsomes
involves preparing the poly(beta-amino alcohols) for hydration,
hydrating the poly(beta-amino alcohols) with agitation, and sizing
the vesicles to achieve a homogenous distribution of liposomes.
Poly(beta-amino alcohols) are first dissolved in an organic solvent
to assure a homogeneous mixture of poly(beta-amino alcohols). The
solvent is then removed to form a polymer-derived film. This
polymer-derived film is thoroughly dried to remove residual organic
solvent by placing the vial or flask on a vaccuum pump overnight.
Hydration of the polymer-derived film is accomplished by adding an
aqueous medium and agitating the mixture. Disruption of LMV
suspensions using sonic energy typically produces small unilamellar
vesicles (SUV) with diameters in the range of 15-50 nm. Lipid
extrusion is a technique in which a lipid/polymer suspension is
forced through a polycarbonate filter with a defined pore size to
yield particles having a diameter near the pore size of the filter
used. Extrusion through filters with 100 nm pores typically yields
large, unilamellar polymer-derived vesicles (LUV) with a mean
diameter of 120-140 nm.
[0181] In certain embodiments, the polynucleotide is an RNA
molecule (e.g., an RNAi molecule). In other embodiments, the
polynucleotide is a DNA molecule. In certain embodiments, the
amount of poly(beta-amino alcohol) in the liposome ranges from
30-80 mol %, preferably 40-70 mol %, more preferably 60-70 mol %.
These liposomes may be prepared using any method known in the art.
In certain embodiments (e.g., liposomes containing RNAi molecules),
the liposomes are prepared by lipid extrusion.
[0182] Certain poly(beta-amino alcohols) can spontaneously self
assemble around certain molecules, such as DNA and RNA, to form
liposomes. In some embodiments, the application is the delivery of
polynucleotides. Use of these poly(beta-amino alcohols) allows for
simple assembly of liposomes without the need for additional steps
or devices such as an extruder.
[0183] The following scientific papers described other methods for
preparing liposomes and micelles: Narang et al., "Cationic Lipids
with Increased DNA Binding Affinity for Nonviral Gene Transfer in
Dividing and Nondividing Cells" Bioconjugate Chem. 16:156-68, 2005;
Hofland et al., "Formation of stable cationic lipid/DNA complexes
for gene transfer" Proc. Natl. Acad. Sci. USA 93:7305-7309, July
1996; Byk et al., "Synthesis, Activity, and Structure--Activity
Relationship Studies of Novel Cationic Lipids for DNA Transfer" J.
Med. Chem. 41(2):224-235, 1998; Wu et al., "Cationic Lipid
Polymerization as a Novel Approach for Constructing New DNA
Delivery Agents" Bioconjugate Chem. 12:251-57, 2001; Lukyanov et
al., "Micelles from lipid derivatives of water-soluble polymers as
delivery systems for poorly soluble drugs" Advanced Drug Delivery
Reviews 56:1273-1289, 2004; Tranchant et al., "Physicochemical
optimisation of plasmid delivery by cationic lipids" J. Gene Med.
6:S24-S35, 2004; van Balen et al., "Liposome/Water Lipophilicity:
Methods, Information Content, and Pharmaceutical Applications"
Medicinal Research Rev. 24(3):299-324, 2004; each of which is
incorporated herein by reference.
Agents to be Delivered
[0184] The agents to be delivered by the systems of the present
invention may be therapeutic, diagnostic, or prophylactic agents.
Any chemical compound to be administered to an individual may be
delivered using the inventive complexes, picoparticles,
nanoparticles, microparticles, micelles, or liposomes. The agent
may be a small molecule, organometallic compound, nucleic acid,
protein, peptide, polynucleotide, metal, an isotopically labeled
chemical compound, drug, vaccine, immunological agent, etc.
[0185] In certain embodiments, the agents are organic compounds
with pharmaceutical activity. In another embodiment of the
invention, the agent is a clinically used drug. In certain
embodiments, the drug is an antibiotic, anti-viral agent,
anesthetic, steroidal agent, anti-inflammatory agent,
anti-neoplastic agent, antigen, vaccine, antibody, decongestant,
antihypertensive, sedative, birth control agent, progestational
agent, anti-cholinergic, analgesic, anti-depressant,
anti-psychotic, .beta.-adrenergic blocking agent, diuretic,
cardiovascular active agent, vasoactive agent, non-steroidal
anti-inflammatory agent, nutritional agent, etc.
[0186] In certain embodiments of the present invention, the agent
to be delivered may be a mixture of agents.
[0187] Diagnostic agents include gases; metals; commercially
available imaging agents used in positron emissions tomography
(PET), computer assisted tomography (CAT), single photon emission
computerized tomography, x-ray, fluoroscopy, and magnetic resonance
imaging (MRI); and contrast agents. Examples of suitable materials
for use as contrast agents in MRI include gadolinium chelates, as
well as iron, magnesium, manganese, copper, and chromium. Examples
of materials useful for CAT and x-ray imaging include iodine-based
materials.
[0188] Prophylactic agents include, but are not limited to,
antibiotics, nutritional supplements, and vaccines. Vaccines may
comprise isolated proteins or peptides, inactivated organisms and
viruses, dead organisms and viruses, genetically altered organisms
or viruses, and cell extracts. Prophylactic agents may be combined
with interleukins, interferon, cytokines, and adjuvants such as
cholera toxin, alum, Freund's adjuvant, etc. Prophylactic agents
include antigens of such bacterial organisms as Streptococccus
pneumoniae, Haemophilus influenzae, Staphylococcus aureus,
Streptococcus pyrogenes, Corynebacterium diphtheriae, Listeria
monocytogenes, Bacillus anthracis, Clostridium tetani, Clostridium
botulinum, Clostridium perfringens, Neisseria meningitidis,
Neisseria gonorrhoeae, Streptococcus mutans, Pseudomonas
aeruginosa, Salmonella typhi, Haemophilus parainfluenzae,
Bordetella pertussis, Francisella tularensis, Yersinia pestis,
Vibrio cholerae, Legionella pneumophila, Mycobacterium
tuberculosis, Mycobacterium leprae, Treponema pallidum,
Leptospirosis interrogans, Borrelia burgdorferi, Camphylobacter
jejuni, and the like; antigens of such viruses as smallpox,
influenza A and B, respiratory syncytial virus, parainfluenza,
measles, HIV, varicella-zoster, herpes simplex 1 and 2,
cytomegalovirus, Epstein-Barr virus, rotavirus, rhinovirus,
adenovirus, papillomavirus, poliovirus, mumps, rabies, rubella,
coxsackieviruses, equine encephalitis, Japanese encephalitis,
yellow fever, Rift Valley fever, hepatitis A, B, C, D, and E virus,
and the like; antigens of fungal, protozoan, and parasitic
organisms such as Cryptococcus neoformans, Histoplasma capsulatum,
Candida albicans, Candida tropicalis, Nocardia asteroides,
Rickettsia ricketsii, Rickettsia typhi, Mycoplasma pneumoniae,
Chlamydial psittaci, Chlamydial trachomatis, Plasmodium falciparum,
Trypanosoma brucei, Entamoeba histolytica, Toxoplasma gondii,
Trichomonas vaginalis, Schistosoma mansoni, and the like. These
antigens may be in the form of whole killed organisms, peptides,
proteins, glycoproteins, carbohydrates, or combinations
thereof.
Targeting Agents
[0189] The inventive complexes, liposomes, micelles,
microparticles, picoparticles and nanoparticles may be modified to
include targeting agents since it is often desirable to target a
particular cell, collection of cells, or tissue. A variety of
targeting agents that direct pharmaceutical compositions to
particular cells are known in the art (see, for example, Cotten et
al., Methods Enzym. 217:618, 1993; incorporated herein by
reference). The targeting agents may be included throughout the
particle or may be only on the surface. The targeting agent may be
a protein, peptide, carbohydrate, glycoprotein, lipid, small
molecule, nucleic acids, etc. The targeting agent may be used to
target specific cells or tissues or may be used to promote
endocytosis or phagocytosis of the particle. Examples of targeting
agents include, but are not limited to, antibodies, fragments of
antibodies, low-density lipoproteins (LDLs), transferrin,
asialycoproteins, gp120 envelope protein of the human
immunodeficiency virus (HIV), carbohydrates, receptor ligands,
sialic acid, aptamers, etc. If the targeting agent is included
throughout the particle, the targeting agent may be included in the
mixture that is used to form the particles. If the targeting agent
is only on the surface, the targeting agent may be associated with
(i.e., by covalent, hydrophobic, hydrogen bonding, van der Waals,
or other interactions) the formed particles using standard chemical
techniques.
Pharmaceutical Compositions
[0190] Once the complexes, micelles, liposomes, or particles have
been prepared, they may be combined with one or more pharmaceutical
excipients to form a pharmaceutical composition that is suitable to
administer to animals including humans. As would be appreciated by
one of skill in this art, the excipients may be chosen based on the
route of administration as described below, the agent being
delivered, time course of delivery of the agent, etc.
[0191] Some aspects of the invention include a pharmaceutical
composition comprising a poly(beta-amino alcohol) polymer of the
formula:
##STR00068##
and a pharmaceutical agent.
[0192] Some aspects of the invention include a pharmaceutical
composition comprising a poly(beta-amino alcohol) polymer of the
formula:
##STR00069##
and a pharmaceutical agent.
[0193] Pharmaceutical compositions of the present invention and for
use in accordance with the present invention may include a
pharmaceutically acceptable excipient or carrier. As used herein,
the term "pharmaceutically acceptable carrier" means a non-toxic,
inert solid, semi-solid or liquid filler, diluent, encapsulating
material or formulation auxiliary of any type. Some examples of
materials which can serve as pharmaceutically acceptable carriers
are sugars such as lactose, glucose, and sucrose; starches such as
corn starch and potato starch; cellulose and its derivatives such
as sodium carboxymethyl cellulose, ethyl cellulose, and cellulose
acetate; powdered tragacanth; malt; gelatin; talc; excipients such
as cocoa butter and suppository waxes; oils such as peanut oil,
cottonseed oil; safflower oil; sesame oil; olive oil; corn oil and
soybean oil; glycols such as propylene glycol; esters such as ethyl
oleate and ethyl laurate; agar; detergents such as Tween 80;
buffering agents such as magnesium hydroxide and aluminum
hydroxide; alginic acid; pyrogen-free water; isotonic saline;
Ringer's solution; ethyl alcohol; and phosphate buffer solutions,
as well as other non-toxic compatible lubricants such as sodium
lauryl sulfate and magnesium stearate, as well as coloring agents,
releasing agents, coating agents, sweetening, flavoring and
perfuming agents, preservatives and antioxidants can also be
present in the composition, according to the judgment of the
formulator. The pharmaceutical compositions of this invention can
be administered to humans and/or to animals, orally, rectally,
parenterally, intracisternally, intravaginally, intranasally,
intraperitoneally, topically (as by powders, creams, ointments, or
drops), bucally, or as an oral or nasal spray.
[0194] Liquid dosage forms for oral administration include
pharmaceutically acceptable emulsions, microemulsions, solutions,
suspensions, syrups, and elixirs. In addition to the active
ingredients (i.e., microparticles, nanoparticles, liposomes,
micelles, polynucleotide/lipid complexes), the liquid dosage forms
may contain inert diluents commonly used in the art such as, for
example, water or other solvents, solubilizing agents and
emulsifiers such as ethyl alcohol, isopropyl alcohol, ethyl
carbonate, ethyl acetate, benzyl alcohol, benzyl benzoate,
propylene glycol, 1,3-butylene glycol, dimethylformamide, oils (in
particular, cottonseed, groundnut, corn, germ, olive, castor, and
sesame oils), glycerol, tetrahydrofurfuryl alcohol, polyethylene
glycols and fatty acid esters of sorbitan, and mixtures thereof.
Besides inert diluents, the oral compositions can also include
adjuvants such as wetting agents, emulsifying and suspending
agents, sweetening, flavoring, and perfuming agents.
[0195] Injectable preparations, for example, sterile injectable
aqueous or oleaginous suspensions may be formulated according to
the known art using suitable dispersing or wetting agents and
suspending agents. The sterile injectable preparation may also be a
sterile injectable solution, suspension, or emulsion in a nontoxic
parenterally acceptable diluent or solvent, for example, as a
solution in 1,3-butanediol. Among the acceptable vehicles and
solvents that may be employed are water, Ringer's solution, U.S.P.
and isotonic sodium chloride solution. In addition, sterile, fixed
oils are conventionally employed as a solvent or suspending medium.
For this purpose any bland fixed oil can be employed including
synthetic mono- or diglycerides. In addition, fatty acids such as
oleic acid are used in the preparation of injectables. In certain
embodiments, the particles are suspended in a carrier fluid
comprising 1% (w/v) sodium carboxymethyl cellulose and 0.1% (v/v)
Tween 80.
[0196] The injectable formulations can be sterilized, for example,
by filtration through a bacteria-retaining filter, or by
incorporating sterilizing agents in the form of sterile solid
compositions which can be dissolved or dispersed in sterile water
or other sterile injectable medium prior to use.
[0197] Compositions for rectal or vaginal administration are
preferably suppositories which can be prepared by mixing the
particles with suitable non-irritating excipients or carriers such
as cocoa butter, polyethylene glycol, or a suppository wax which
are solid at ambient temperature but liquid at body temperature and
therefore melt in the rectum or vaginal cavity and release the
particles.
[0198] Solid dosage forms for oral administration include capsules,
tablets, pills, powders, and granules. In such solid dosage forms,
the particles are mixed with at least one inert, pharmaceutically
acceptable excipient or carrier such as sodium citrate or dicalcium
phosphate and/or a) fillers or extenders such as starches, lactose,
sucrose, glucose, mannitol, and silicic acid, b) binders such as,
for example, carboxymethylcellulose, alginates, gelatin,
polyvinylpyrrolidinone, sucrose, and acacia, c) humectants such as
glycerol, d) disintegrating agents such as agar-agar, calcium
carbonate, potato or tapioca starch, alginic acid, certain
silicates, and sodium carbonate, e) solution retarding agents such
as paraffin, f) absorption accelerators such as quaternary ammonium
compounds, g) wetting agents such as, for example, cetyl alcohol
and glycerol monostearate, h) absorbents such as kaolin and
bentonite clay, and i) lubricants such as talc, calcium stearate,
magnesium stearate, solid polyethylene glycols, sodium lauryl
sulfate, and mixtures thereof. In the case of capsules, tablets,
and pills, the dosage form may also comprise buffering agents.
[0199] Solid compositions of a similar type may also be employed as
fillers in soft and hard-filled gelatin capsules using such
excipients as lactose or milk sugar as well as high molecular
weight polyethylene glycols and the like.
[0200] The solid dosage forms of tablets, dragees, capsules, pills,
and granules can be prepared with coatings and shells such as
enteric coatings and other coatings well known in the
pharmaceutical formulating art. They may optionally contain
opacifying agents and can also be of a composition that they
release the active ingredient(s) only, or preferentially, in a
certain part of the intestinal tract, optionally, in a delayed
manner. Examples of embedding compositions which can be used
include polymeric substances and waxes.
[0201] Solid compositions of a similar type may also be employed as
fillers in soft and hard-filled gelatin capsules using such
excipients as lactose or milk sugar as well as high molecular
weight polyethylene glycols and the like.
[0202] Dosage forms for topical or transdermal administration of an
inventive pharmaceutical composition include ointments, pastes,
creams, lotions, gels, powders, solutions, sprays, inhalants, or
patches. The particles are admixed under sterile conditions with a
pharmaceutically acceptable carrier and any needed preservatives or
buffers as may be required. Ophthalmic formulation, ear drops, and
eye drops are also contemplated as being within the scope of this
invention.
[0203] The ointments, pastes, creams, and gels may contain, in
addition to the particles of this invention, excipients such as
animal and vegetable fats, oils, waxes, paraffins, starch,
tragacanth, cellulose derivatives, polyethylene glycols, silicones,
bentonites, silicic acid, talc, and zinc oxide, or mixtures
thereof.
[0204] Powders and sprays can contain, in addition to the particles
of this invention, excipients such as lactose, talc, silicic acid,
aluminum hydroxide, calcium silicates, and polyamide powder, or
mixtures of these substances. Sprays can additionally contain
customary propellants such as chlorofluorohydrocarbons.
[0205] Transdermal patches have the added advantage of providing
controlled delivery of a compound to the body. Such dosage forms
can be made by dissolving or dispensing the microparticles or
nanoparticles in a proper medium. Absorption enhancers can also be
used to increase the flux of the compound across the skin. The rate
can be controlled by either providing a rate controlling membrane
or by dispersing the particles in a polymer matrix or gel.
[0206] These and other aspects of the present invention will be
further appreciated upon consideration of the following Examples,
which are intended to illustrate certain particular embodiments of
the invention but are not intended to limit its scope, as defined
by the claims.
EXAMPLES
[0207] Using combinatorial polymerization, a new class of novel
cationic polymers, poly(.beta.-amino alcohols) (PBAAs), were
synthesized which can be used as coatings for biomedical devices.
Moreover, these polymers covered a wide range of chemical
functionality and can be used to study the effect of surface
chemistry on the foreign body responses. Through an initial in
vitro screening, the polymer coatings that promoted or inhibited
the activation of mouse monocyte/macrophage cells were identified
by measuring the secretion of a pro-inflammatory cytokine, tumor
necrosis factor .alpha. (TNF-.alpha.). The polymers that induced
highest and lowest levels of TNF-.alpha. secretion were used to
coat carboxylated polystyrene microparticles, which were
subsequently injected into mice subcutaneously. Twenty four hours
after injection, significantly different levels of inflammatory
cell recruitment into the implantation sites were observed using
live animal imaging. Histological analysis of fibrosis around the
particles 30 days after injections showed correlation with both the
in vitro and live imaging results.
Example 1
Polymer Synthesis and Characterization
[0208] A large number of chemically diverse cationic polymers were
synthesized using combinatorial polymerization. The monomers used
to make the poly(beta-amino alcohols) were purchased from
Sigma-Aldrich (Milwaukee, Wis.), TCI America (Portland, Oreg.) and
Acros Organics (Fisher Scientific, Pittsburgh, Pa.). All the
epoxide and amine monomers used in these Examples are liquid at
room temperature. The polymerizations took place in bulk at room
temperature under vigorous stirring until solidification typically
within twenty-four hours. Solvents such as dimethyl sulfoxide
(DMSO) or dichloromethane could also be used but were not required
for the reactions. To ensure all the polymers were terminated with
amines, the molar ratio between amines and epoxides were controlled
to be 1 to 1.2 in the polymerization. The polymers that were not
soluble in water or form hydrogels with water were eliminated in
the subsequent coatings. The molecular weights of representative
PBAAs were determined using cationic columns in a Viscotek Gel
Permeation Chromatography. A 2.7% acetic acid solution was used as
the running solvent and the molecular weights were calculated
relative to polyethyleneimine (PEI) standards. The polymers were
also characterized using a 400 MHz NMR Bruker Avance 400. The
solvent was deuterated DMSO or chloroform.
Example 2
Surface Coatings and Characterization
[0209] The PBAA solutions for coatings were made by dissolving the
polymers in either DI water or slightly acidic solution at the
concentration of 0.01 mol/L by repeating unit. The pHs of the
solutions were measured using a bench-top pH meter (Mettler
Toledo). The solutions were coated on 96-well glass-bottom plates
(Matrix Technologies Corp.) for in vitro screening. Each well was
soaked with 150 .mu.L different PBAA solutions for 1 hour. The
wells were then washed thoroughly with DI water 5 times. The
coatings were characterized with a Kratos Axis Ultra X-ray
photoelectron spectrometer (XPS) (Kratos Analytical) with a
monochromatized A1 KR X-ray source. The takeoff angle relative to
the sample substrate for this measurement was located at
90.degree.. This means that the effective sampling depth is about a
few nanometers. We seek only a qualitative confirmation of the
surface coating at this stage, no attempt was made to obtain an
accurate estimate of the actually surface coverage and coating
thickness. The XPS signal from the nitrogen in the PBAA was used to
confirm the surface coatings. For in vivo tests, the PBAAs were
coated on carboxylated polystyrene microspheres (20 .mu.m diameter,
PolySciences Inc.) The as-received microspheres were first washed
with DI water 6 times and then incubated in 0.01 mol/L PBAA
solutions for 2 hours for complete electrostatic bonding. The
particles were washed again with DI water for 6 times and finally
dispersed in PBS at a 10% (w/v) concentration for subsequent
injections.
Example 3
In Vitro Screening
[0210] For in vitro screening, the PBAA coated glass-bottom plates
were first sterilized using 70% ethanol for 10 minutes and washed
thoroughly with PBS. RAW 264.7 cells (ATCC) were cultured in DMEM
supplemented with 10% fetal calf serum and penicillin/streptomycin
(all from Invitrogen). Cells were seeded at a density of 150,000
cells/cm.sup.2 on polymer-coated glass surfaces in serum containing
media, incubated at 37.degree. C. for 18 h, and then analyzed for
release of TNF-.alpha. and cell viability. To assess for
TNF-.alpha., cell culture supernatant was removed and analyzed by
ELISA (kit from R&D Systems) according to the manufacturer's
instructions. Briefly, 96-well ELISA plates (BD Falcon) were coated
with capture antibody overnight at 4.degree. C. Plates were then
washed three times with 0.01% Tween in PBS, blocked with 1% BSA in
PBS, and then incubated with samples. After thorough washing, the
captured TNF-.alpha. was detected using a detection antibody,
HRP-conjugated streptavidin, and Ultra-TMB substrate (Pierce). The
reaction was stopped with 0.16M sulfuric acid, and absorbance at
490 nm was determined using a Spectramax plate reader (Molecular
Devices). To assay for cell viability, cells were incubated with
MTS
([3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfopheny-
l)-2H-tetrazolium) reagent (Promega) for 2 hours at 37.degree. C.,
and absorbance at 490 nm was measured. Visualization of live and
dead cells was performed by staining with calcein and ethidium
homodimer-1, respectively (Invitrogen). Fluorescence was visualized
on a Zeiss inverted microscope equipped with a 20.times. objective.
Images were acquired using AxioVision software. All experiments
were performed in triplicate and error bars indicate standard
deviation from the mean. The cell morphology was further observed
with a JEOL-6060SEM (JEOL Ltd., Japan) scanning electron microscope
(SEM). The cells were first fixed using 4% formaldehyde solution
for 30 minutes after being washed with PBS twice. The fixed samples
were then rinsed with DI water and dehydrated using a sequence of
progressively more concentrated ethanol solutions (30%, 50%, 70%,
90% and 100%). After a few hours of air-drying, the cells were
sputter-coated with a 2-3 nm layer of gold for imaging by use of a
Desk II cold sputter/etch unit (Denton Vacuum LLC).
Example 4
In Vivo Imaging
[0211] The PBAA coated microparticles were injected subcutaneously
in an array format on the backs of immunocompetent hairless mice
(SKH1, Charles River Laboratories, Wilmington, Mass.). Each
injection contained 100 .mu.L 10% (w/v) particle suspension in PBS.
The mice were anesthetized with isoflurane inhalation and their
backs were scrubbed with alcohol patches before the injections. In
vivo fluorescence and bioluminescence imaging was performed by
using an IVIS imaging system (IVIS Spectrum, Caliper Life Sciences,
Hopkinton, Mass.) and the images were analyzed with Living Image
acquisition and analysis software (Caliper Life Sciences,
Hopkinton, Mass.). The Prosense.RTM.750 (VisEn Medica, Woburn,
Mass.) was injected through the tail vein (i.v.) at a dose of 100
.mu.L per mouse 24 hours before imaging. Luminol (Aldrich) was
injected into intraperitoneal (i.p.) space 20 minutes before
imaging at a dose of 5 mg per mouse. The mice were anesthetized
with isoflurane for the i.p. injection and imaging. Histological
Analysis Mice were euthanized using CO.sub.2 gas. Skin samples
containing the injected microparticles were fixed in AccuStain
(Aldrich), embedded in paraffin, sectioned and stained with Masson
Trichrome based on standard procedures. The histology slides were
then observed using a Zeiss inverted microscope. Images at both
5.times. and 20.times. were taken to view the global fibrosis
around the entire implantation site as well as local fibrosis
around individual particles.
Example 5
In Vitro Screening
[0212] A significant concern with respect to these cationic polymer
coatings is their cytotoxicity. Furthermore, it was unknown whether
the differences in TNF-.alpha. observed could be attributed to
differences in cell viability. Using an MTS assay to measure cell
viability, we found that although the different PBAA coatings
exhibited significantly different levels of macrophage activation,
cell viability on all surfaces were essentially the same and
comparable to cells seeded on control surfaces, as shown in FIG.
2A. Fluorescent live/dead staining assay further confirmed that the
cells all remained alive whether they were activated on the
uncoated surface or not activated on the PBAA-coated surface.
(FIGS. 2B and 2C) The morphologies of the cells seeded on different
surfaces were dramatically different, and the trends were similar
to that observed by SEM.
[0213] To investigate the stability of the polymer coating, we
performed X-ray photoelectron spectroscopy (XPS), as shown in FIG.
2E. From the signals of N1s, characteristic peak for tertiary amine
groups in PBAAs, we found that the coated surfaces, as prepared or
presoaked with PBS for twenty-four hours, both have the same amount
of PBAA coatings, while the uncoated glass surface has no
detectable N1s signal, as expected. To confirm that the activation
of macrophages was influenced solely by the surface coatings,
further control experiments with 3 inhibitory PBAAs were performed.
We incubated surfaces that had been coated with polymers with media
for twenty-four hours, and then examined the amount of TNF-.alpha.
secreted by cells seeded on the normal coatings, on the coatings
that have been pre-soaked with media for twenty-four hours, and on
the uncoated surfaces but incubated with media that had been
preconditioned with the coated surfaces for twenty-four hours. The
controls in all three cases were uncoated surfaces. From the
results shown in FIG. 2D, we see that cells seeded on PBAA-coated
surfaces that had been pre-soaked with media still secreted low
levels of TNF-.alpha., similar to cells seeded on surfaces coated
normally with PBAA. Furthermore, cells seeded on uncoated surfaces
and incubated with media that had been pre-conditioned secreted
high levels of TNF-.alpha., similar to cells seeded on uncoated
surfaces and incubated with normal media. These results suggest
that the coatings rather than any possible polymers dissolved in
the media were responsible for the inhibition of TNF-.alpha.
secretion.
[0214] To first screen the effect of different PBAA coatings on
monocyte/macrophage activation, we immobilized the polymers on
96-well plates with glass bottoms. The glass surfaces, which are
generally hydrophilic and negatively charged under physiological
conditions, have been commonly used to immobilize polycations and
build multilayer polyelectrolyte coatings (J. D. Mendelsohn, S. Y.
Yang, J. A. Hiller, A. I. Hochbaum, M. F. Rubner, Biomacromolecules
2003, 4, 96.) For the in vitro screen, we measured the response of
a mouse monocyte/macrophage cell line to the coatings. It is
generally thought that macrophages are one of the dominant cell
types that regulate foreign body responses. (J. M. Anderson,
Cardiovasc. Pathol. 1993, 2, S33) The behavior of macrophages on
surfaces with different charge densities, (J. A. Hunt, B. F.
Flanagan, P. J. McLaughlin, I. Strickland, D. F. Williams, J.
Biomed. Mater. Res. 1996, 31, 139) topography (A. K. Refai, M.
Textor, D. M. Brunette, J. D. Waterfield, J. Biomed. Mater. Res.
2004, 70A, 194; N. E. Paul, et al., Biomaterials 2008, 29, 4056)
and modulus (E. F. Irwin, K. Saha, M. Rosenbluth, L. J. Gamble, D.
G. Castner, K. E. Healy, J. Biomater. Sci. Polymer Edn 2008, 19,
1363) has been widely studied. It was found in particular that the
surface chemistry (W. G. Brodbeck, Y. Nakayama, T. Matsuda, E.
Colton, N. P. Ziats, J. M. Anderson, Cytokine, 2002, 18, 311; R. J.
Schutte, A. Parisi-Amon, W. M. Reichert, J. Biomed. Mater. Res.
2009, 88A, 128; S. Kamath, D. Bhattacharyya, C. Padukudru, R. B.
Timmons, L. Tang, J. Biomed. Mater. Res. 2008, 86A, 617) has direct
influence on the macrophage-material interactions, although the
chemical diversity of the surface chemistries that have been
explored is very limited. Moreover, there is often a lack of in
vivo studies to correlate the in vitro results.
[0215] The response of the monocyte/macrophage cells to different
cationic polymer coatings were assessed by measuring the
TNF-.alpha. concentration in the cell culture media 18 hours after
cell seeding. TNF-.alpha. is one of the most important
pro-inflammatory cytokines and plays a role in further recruitment
and activation of inflammatory cells. The level of TNF-.alpha.
secreted is an indicator of the macrophage activation. FIG. 2A
shows the relative TNF-.alpha. concentration secreted by cells
seeded on several of the coatings that were tested. The uncoated
glass-bottom well is used as a control. PLL and PAH, two typical
commercially available cationic polymers, were used as additional
references. Cells seeded on the best PBAAs showed a 10-fold lower
level of TNF-.alpha. compared to cells seeded on the control,
uncoated glass surface, and 35-fold decrease compared to cells on
the PLL coating. Scanning electron microscope (SEM) images revealed
dramatic differences in cell morphology, as shown in FIGS. 2B and
2C. Cells that secreted high levels of TNF-.alpha. were
well-spread, whereas cells that secreted low levels of TNF-.alpha.
remained rounded. Remarkably, the PBAAs that promoted the
macrophage activation were all made from similar amine monomers
(#22, #35, #36) that contain dimethoxy, diethoxy or dioxolane
groups, while the PBAAs that inhibited cell activation contained at
least two tertiary amines per repeating unit (e.g., A10, A12, B20
and B30). The most inhibitory PBAA was A12-which has three tertiary
amine groups for every repeating unit. While the mechanism by which
the chemical functional groups affect macrophage activation is not
clear at this stage, it is possible that the composition and
conformation of proteins adsorbed on the surface dictates the
behavior of monocyte/macrophage cells.
Example 6
In Vivo Test
[0216] To examine the inflammatory response to these novel
materials in vivo, four different PBAAs that induced the highest
(A35 and B35) and lowest (A12 and B12) levels of TNF-.alpha.
secretion were chosen to coat 20 .mu.m carboxylated polystyrene
beads. FIG. 3A shows a SEM image of the beads with a schematic
illustrating the coating. The size of the bead was selected to be
large enough to limit phagocytosis but small enough to allow easy
injection under the skin. The chemical structures of A12 and B35
are shown in FIG. 3B, and the configuration of the injections is
shown by a schematic in FIG. 3C. To measure the early foreign body
responses to the injected beads, we examined the inflammatory
response to beads coated with different PBAAs in live animals using
two different imaging probes, Prosense.RTM.750 and luminol.
Prosense is fluorescence sensor that measures the activity of
Cathepsin B (and to a lesser extent Cathepsins K, L, and S) (M.
Nahrendorf, D. E. Sosnovik, P. Waterman, F. K. Swirski, A. N.
Pande, E. Aikawa, J-L. Figueiredo, M. J. Pittet, R. Weissleder,
Circ. Res. 2007, 100, 1218). The fluorescence signal correlates
with the presence of neutrophils and monocyte/macrophages and can
be used to assess the acute inflammatory response (K. M. Bratlie,
T. T. Dang, S. Lyle, M. Nahrendorf, R. Weissleder, R. Langer, D. G.
Anderson, PLoS ONE 2010, 5, e10032). FIG. 3D shows the fluorescent
images obtained using Prosense 24 hours after the particle
injections. Quantification of the fluorescent images show that A12
and B 12 have lower signals than the A35 and B35, consistent with
the trends observed in vitro. Similar results were observed using
luminol, a bioluminescent compound that reacts with reactive oxygen
species (ROS) and emits blue luminescence (S. Gross, S. T. Gammon,
B. L. Moss, D. Rauch, J. Harding, J. W. Heinecke, L. Ratner, D.
Piwnica-Worms, Nature Medicine 2009, 15, 455). It is known that
during inflammation in response to foreign bodies, neutrophils and
macrophages release ROS, and therefore luminol has been used to
measure the the inflammatory response to implanted biomaterials (W.
F. Liu et al.). The luminescent images obtained with luminol are
shown in FIG. 3E and confirm again the correlation of the early
foreign body responses with the in vitro screening results.
Example 7
Histological Analyses
[0217] Histological analysis of skin tissue 30 days after injection
of the most inflammatory coating B35 and the least inflammatory
coating A12 as well as uncoated control is shown in FIGS. 4A to 4C.
The Masson trichrome-stained collagen, which indicates fibrosis,
appears blue in these micrographs. The low magnification images
show that the fibrosis around the entire implantation site occurred
in all three cases. This is the usual response of the body to the
continuous presence of foreign materials. However, interestingly,
fibrosis around individual particles was significantly different as
shown by the high magnification images. From the density of
deposited collagen or amount of blueness in the images, it is clear
that relative to the control uncoated beads, there is less fibrosis
around particles with the A12 coating, and more around particles
with the B35 coating. This difference is a direct reflection of the
effect of surface coatings on the foreign body response, and is
consistent with the results from in vitro and live animal imaging
experiments.
Other Embodiments
[0218] Having now described some illustrative embodiments of the
invention, it should be apparent to those skilled in the art that
the foregoing is merely illustrative and not limiting, having been
presented by way of example only. Numerous modifications and other
illustrative embodiments are within the scope of one of ordinary
skill in the art and are contemplated as falling within the scope
of the invention. In particular, although many of the examples
presented herein involve specific combinations of method acts or
system elements, it should be understood that those acts and those
elements may be combined in other ways to accomplish the same
objectives. Acts, elements, and features discussed only in
connection with one embodiment are not intended to be excluded from
a similar role in other embodiments. Further, for the one or more
means-plus-function limitations recited in the following claims,
the means are not intended to be limited to the means disclosed
herein for performing the recited function, but are intended to
cover in scope any means, known now or later developed, for
performing the recited function. Use of ordinal terms such as
first, second, third, etc., in the claims to modify a claim element
does not by itself connote any priority, precedence, or order of
one claim element over another or the temporal order in which acts
of a method are performed, but are used merely as labels to
distinguish one claim element having a certain name from another
element having a same name (but for use of the ordinal term) to
distinguish the claim elements. Similarly, use of a), b), etc., or
i), ii), etc. does not by itself connote any priority, precedence,
or order of steps in the claims. Similarly, the use of these terms
in the specification does not by itself connote any required
priority, precedence, or order.
[0219] This application refers to various issued patents, published
patent applications, journal articles, books, manuals, and other
publications, all of which are incorporated herein by
reference.
[0220] The foregoing written specification is considered to be
sufficient to enable one skilled in the art to practice the
invention. The present invention is not to be limited in scope by
examples provided, since the examples are intended as a single
illustration of one aspect of the invention and other functionally
equivalent embodiments are within the scope of the invention.
Various modifications of the invention in addition to those shown
and described herein will become apparent to those skilled in the
art from the foregoing description and fall within the scope of the
appended claims. The advantages and objects of the invention are
not necessarily encompassed by each embodiment of the
invention.
* * * * *