U.S. patent application number 12/979006 was filed with the patent office on 2011-04-21 for separating agent for optical isomers and separation column for optical isomers.
Invention is credited to Dieter Lubda, Tatsushi MURAKAMI, Akihiro Nakanishi, Michael Schulte.
Application Number | 20110089095 12/979006 |
Document ID | / |
Family ID | 36498146 |
Filed Date | 2011-04-21 |
United States Patent
Application |
20110089095 |
Kind Code |
A1 |
MURAKAMI; Tatsushi ; et
al. |
April 21, 2011 |
SEPARATING AGENT FOR OPTICAL ISOMERS AND SEPARATION COLUMN FOR
OPTICAL ISOMERS
Abstract
This invention provides a separating agent for optical isomers,
which has high asymmetry recognition ability and can be used
particularly at a high flow rate when used for the separation of
the optical isomers, and a separation column for optical isomers
having the same. This invention provides: a separating agent for
optical isomers which is used for separation of optical isomers in
a sample comprising the optical isomers, which is comprising a
monolithic inorganic type carrier having a meso pore formed on an
inner wall surface of a specific macropore, and a polysaccharide or
a polysaccharide derivative supported on the monolithic inorganic
type carrier, wherein the meso pore has a pore size of 6 to 100 nm;
and a separation column for optical isomers in which the separating
agent for optical isomers is held in a column tube.
Inventors: |
MURAKAMI; Tatsushi;
(Myoko-shi, JP) ; Nakanishi; Akihiro;
(Tsukuba-shi, JP) ; Lubda; Dieter; (Bensheim,
DE) ; Schulte; Michael; (Bischofsheim, DE) |
Family ID: |
36498146 |
Appl. No.: |
12/979006 |
Filed: |
December 27, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11806033 |
May 29, 2007 |
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12979006 |
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PCT/JP2005/021913 |
Nov 29, 2005 |
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11806033 |
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Current U.S.
Class: |
210/198.2 ;
502/404 |
Current CPC
Class: |
B01J 20/286 20130101;
B01J 20/3272 20130101; B01J 20/29 20130101; G01N 30/52 20130101;
G01N 2030/528 20130101 |
Class at
Publication: |
210/198.2 ;
502/404 |
International
Class: |
B01J 20/285 20060101
B01J020/285; B01D 15/38 20060101 B01D015/38 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 29, 2004 |
JP |
2004-343683 |
Claims
1. A separating agent for optical isomers which is used for
separation of optical isomers in a sample comprising the optical
isomers, which separating agent comprises a monolithic inorganic
type carrier, and at least one of a polysaccharide and a
polysaccharide derivative supported on the monolithic inorganic
type carrier, wherein: the monolithic inorganic type carrier
comprises a porous body in which channels are formed through
connection of cavities from one end to the other end of the
monolithic inorganic type carrier; the cavities each comprise a
macropore and a meso pore formed on an inner wall surface of the
macropore; the macropore has a pore size of 0.5 to 30 .mu.m; the
meso pore has a pore size of 20 to 50 nm; and the polysaccharide is
cellulose.
2. The separating agent for optical isomers according to claim 1,
wherein the macropore has a pore size of 0.5 to 10 .mu.m.
3. The separating agent for optical isomers according to claim 2,
wherein the macropore has a pore size of 1.0 to 6.0 .mu.m.
4. The separating agent for optical isomers according to claim 1,
wherein the monolithic inorganic type carrier is mainly composed of
silica.
5. The separating agent for optical isomers according to claim 1,
wherein the polysaccharide derivative is one of an ester derivative
of cellulose and a carbamate derivative of cellulose.
6. A separation column for optical isomers comprising a column tube
and the separating agent for optical isomers according to claim 1
or 2 which is held in the column tube.
Description
CROSS REFERENCE
[0001] The present application is a divisional application based
upon application Ser. No. 11/806,033, filed on May 29, 2007, to
which priority is claimed under 35 U.S.C. .sctn.120. Application
Ser. No. 11/806,033 is a continuation of international application
PCT/JP2005/021913, filed on Nov. 29, 2005, which designated the
United States, to which priority is also claimed under 35 U.S.
.sctn.120. This application claims priority under 35 U.S.C.
.sctn.119(a) to patent application no. 2004-343683 filed in Japan
on Nov. 29, 2004. The contents of each of the foregoing
applications is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a separation column for
optical isomers, and more particularly to a separation column for
optical isomers used for separation of the optical isomers by
chromatography. In particular, the invention relates to a
separation column for optical isomers which efficiently separates a
broad range of compounds in the separation of pharmaceuticals,
foods, agricultural chemicals and perfumes.
[0004] 2. Description of Related Art
[0005] Optical isomers having a relationship of a real image and a
mirror image have the same physical and chemical properties such as
a boiling point, a melting point, and solubility, but often show
differences in interactions for a living matter such as a bioactive
including taste and odor. In particular, in the field of
pharmaceutical preparations, there are significant differences in
an effect of a medicine and toxicity between the two optical
isomers. Therefore, in the Guideline for the Production of
Pharmaceuticals, the Ministry of Health, Labor and Welfare
describes that "when a drug is a racemic modification, it is
desirable to preliminarily study absorption, distribution,
metabolism and movement of excretion for each isomer".
[0006] As stated above, optical isomers have completely the same
physical and chemical properties such as a boiling point, a melting
point, and solubility, therefore, each optical isomer could not be
separated by classical, ordinary separation means and it was not
possible to study on interaction of an individual optical isomer
with the living matter. Thus, energetic studies have been made on
techniques for separating optical isomers in order to analyze a
wide variety of optical isomers conveniently with high
precision.
[0007] And as a separation technique that meets these requirements,
an optical resolution method by high performance liquid
chromatography (HPLC), in particular an optical resolution method
by separation columns for optical isomers for HPLC has progressed.
As the separation columns for optical isomers referred to herein, a
chiral stationary phase composed of an asymmetry recognition agent
itself or a chiral stationary phase composed of an asymmetry
recognition agent supported on a suitable carrier is used.
[0008] Known examples of the asymmetry recognition agent include
optical active triphenylmethyl polymethacrylate (see e.g., JP
57-150432 A), cellulose, amylose derivatives (see, e.g. , Okamoto
Y., Kawashima M., and Hatada K., J. Am. Chem. Soc., 106:5357,
1984), and ovomucoid which is protein (see e.g., JP 63-307829
A).
[0009] Meanwhile, in a column configured by filling a particulate
inorganic type filler such as silica gel into a tube, resistance to
flow of fluid is first increased and thus pressure drop is
increased. Consequently, a flow per unit time period is reduced,
and a long time is required for the separation when used as
chromatography. Additionally, since the flow per unit time period
is small, productivity per unit time period is small, and generally
it has not been adequate to mass production of separation
subjects.
[0010] As a column to dissolve this drawback, a column made up of a
monolithic inorganic type porous body (see e.g., JP 6-265534 A) has
been known. As a method of producing such a column made up of an
monolithic inorganic type porous body, the method of sealing a
space between the inorganic type porous body and a column tube by
softening plastic or glass with heat has been known (see e.g., JP
2002-505005 A). Moreover, a separation column for optical isomers
where cyclodextrin as an asymmetry recognition agent is chemically
bound to a monolithic inorganic type porous body has been known
(see e.g., JP 2000-515627 A).
[0011] However, in the manufacture of currently known separation
columns for optical isomers using the monolithic inorganic type
porous body, there are some cases where reactivity of the
monolithic inorganic type porous body with the asymmetry
recognition agent is low. Besides, there are some cases where the
asymmetry recognition agent chemically bound to the monolithic
inorganic type porous body is decomposed at the manufacture of
columns. Depending on conditions of the column manufacture, the
asymmetry recognition agent used is sometimes limited and there are
some cases where the column cannot be applied to a broad range of
optical isomers. There have been problems described above in the
manufacture of the separation columns for optical isomers, and
tasks still remain for practical application thereof.
SUMMARY OF THE INVENTION
[0012] It is an object of the invention to provide a separating
agent for optical isomers which has high asymmetry recognition
ability and can be used particularly at a high flow rate when used
for the separation of the optical isomers, and a separation column
for optical isomers having the same.
[0013] As a result of an intensive study on a separating agent for
optical isomers having characteristic asymmetry recognition
ability, the inventors of the present invention have accomplished
the present invention.
[0014] That is, the present invention is a separating agent for
optical isomers which is used for separation of optical isomers in
a sample comprising the optical isomers, which is comprising a
monolithic inorganic type carrier, and at least one of a
polysaccharide and a polysaccharide derivative supported on the
monolithic inorganic type carrier, wherein: the monolithic
inorganic type carrier comprises a porous body in which channels
are formed through connection of cavities from one end to the other
end of the monolithic inorganic type carrier; the cavities each
comprise a macropore and a meso pore formed on an inner wall
surface of the macropore; and the meso pore has a pore size of 6 to
100 nm.
[0015] Further, the present invention provides a separation column
for optical isomers, comprising: a column tube; and the
above-mentioned separating agent for optical isomers which is held
in the column tube.
[0016] According to the present invention, a monolithic inorganic
type carrier having a specific meso pore formed on the inner wall
surface of the macropore is used, and at least one of a
polysaccharide and a polysaccharide derivative capable of
separating optical isomers is supported on the monolithic inorganic
type carrier. Thus, the present invention provides a separating
agent for optical isomers having high asymmetry identifying ability
and a separation column for optical isomers which can be used in
separation, analysis, and fractionation of a wide variety of
optical isomers at a high flow rate.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0017] Hereinafter, an embodiment of the invention is illustrated
in detail.
[0018] The separating agent for optical isomers of the invention
has a porous monolithic inorganic type carrier and polysaccharide
or a derivative thereof supported on this monolithic inorganic type
carrier. In the invention, the polysaccharide or the derivative
thereof may be directly supported on the monolithic inorganic type
carrier, or may be supported through another compound which is
appropriate.
[0019] The monolithic inorganic type carrier is generally a
cylindrical inorganic type porous body which may be held in a
column tube and has a flow path formed through connection of
cavities from one end to the other end of the monolithic inorganic
type carrier. That is, the monolithic inorganic type carrier is
different from a particulate carrier filled in the column tube.
[0020] The monolithic inorganic type carrier preferably contains
silica as a major ingredient, but may be comprised of another
inorganic material and may contain a small amount of an organic
material. When silica is the major ingredient, it is desirable that
surface treatment is given to the monolithic inorganic type carrier
in order to exclude an effect of a residual silanol group, but
there is no problem even if the surface treatment is not given.
[0021] The monolithic inorganic type carrier may employ a known
inorganic type carrier or an improved article thereof.
[0022] Examples thereof include: a porous shaped body described in
JP 2000-515627 A; a monolithic adsorbent described in JP
2002-505005 A; and an inorganic porous column described in JP
H06-265534 A.
[0023] The monolithic inorganic type carrier can be made by known
methods and methods according thereto. The monolithic inorganic
type carrier can be manufactured by, for example, a sol-gel method
where a structure with a solvent rich phase which becomes a huge
void is caused by using metal alkoxide as a starting material and
adding an appropriate coexisting substance such as a polymer such
as polyoxyethylene which dissolves in a solvent to the material as
described in JP 7-41374 A.
[0024] The cavities forming the channels each have a macropore and
a meso pore formed on an inner surface wall of the macropore. A
pore size of the macropore may be controlled in accordance with a
particle size of the coexisting substance, for example. A pore size
of the meso pore may be controlled by solidifying a product of the
sol-gel method and then immersing the product in an acidic aqueous
solution or a basic aqueous solution, for example.
[0025] The macropore is not particularly limited so long as the
pore forms channels passing through the monolithic inorganic type
carrier along a direction of a flow of a mobile phase when the
monolithic inorganic type carrier is provided in a flow path of the
mobile phase. The channels formed through connecting of the
macropores may consist of pores in a straight line or pores
continuing in a three dimensional network. The channels preferably
consists of the pores continuing in a three dimensional network
from the viewpoint of improving separation performance.
[0026] Too small a pore size of the macropore may cause
difficulties in sufficiently supporting on a monolithic inorganic
type carrier a polysaccharide or a polysaccharide derivative for
separating optical isomers. Too large a pore size of the macropore
may result in insufficient performance of separating optical
isomers. From such viewpoints, a pore size of the macropore is
preferably 0.5 to 30 .mu.m, more preferably 0.5 to 10 .mu.m,
futhermore preferably 1.0 to 6.0 .mu.m, still more preferably 1.0
to 4.5 .mu.m.
[0027] Too small a pore size of the meso pore may result in:
[0028] difficulties in sufficiently supporting on the monolithic
inorganic type carrier a polysaccharide or a polysaccharide
derivative for separating optical isomers; prevention of optical
isomers in a sample from sufficiently approaching a polysaccharide
or a polysaccharide derivative; and insufficient separation of
optical isomers by a polysaccharide or a polysaccharide derivative.
A pore size of the meso pore can be increased to a level (several
hundred nm) distinguished from that of the macropore. However, too
large a pore size of the meso pore may result in: a reduced effect
of surface area expansion by providing the meso pore; a reduced
amount of a polysaccharide or a polysaccharide derivative supported
on a monolithic inorganic type carrier; and insufficient separation
of optical isomers by a polysaccharide or a polysaccharide
derivative. From the above viewpoints, a pore size of the meso pore
is preferably 6 to 100 nm, more preferably 15 to 80 nm, furthermore
preferably 20 to 60 nm, and still more preferably 20 to 50 nm.
[0029] The pore size of the macropore can be represented by a value
which can represent a substantial pore size of the macropore in the
monolithic inorganic type carrier. For example, the pore size of
the macropore can be represented by the median of the pore size
distribution of the macropore in the monolithic inorganic type
carrier. The pore size distribution of the macropore can be
measured by using mercury porosimetry or raster electron
microscope.
[0030] The pore size of the meso pore can be represented by a value
which can represent a substantial pore size of the meso pore in the
monolithic inorganic type carrier. For example, the pore size of
the meso pore can be represented by the median of the pore size
distribution of the meso pore in the monolithic inorganic type
carrier. The pore size distribution of the meso pore can be
measured by using mercury porosimetry, BET method with nitrogen
adsorption, or inverse exclusion chromatography (ISEC).
[0031] In particular, the monolithic inorganic type carrier has a
macropore having a pore size of 0.5 to 10 .mu.m and a meso pore
having a pore size of 15 to 80 nm, preferably a macropore having a
pore size of 1.0 to 6.0 .mu.m and a meso pore having a pore size of
20 to 60 nm, more preferably a macropore having a pore size of 1.0
to 4.5 .mu.m and a meso pore having a pore size of 20 to 50 nm.
[0032] The polysaccharide may be any of synthetic polysaccharide,
naturally occurring polysaccharide and naturally occurring modified
polysaccharide, and may be any polysaccharide so long as it is
optically active, but those with high regularity of binding manner
are preferable, and chain-shaped ones are also preferable.
[0033] Examples of the polysaccharide include: .beta.-1,4-glucan
(cellulose), .alpha.-1,4-glucan (amylose or amylopectin),
.alpha.-1,6-glucan (dextran), .beta.-1,6-glucan (pustulan),
.beta.-1,3-glucan (such as curdlan and schizophyllan),
.alpha.-1,3-glucan, .beta.-1,2-glucan (Crown Gall polysaccharide),
.beta.-1,4-galactan, .beta.-1,4-mannan, .alpha.-1,6-mannan,
.beta.-1,2-fructan (inulin), .beta.-2,6-fructan (levan),
.beta.-1,4-xylan, .beta.-1,3-xylan, .beta.-1,4-chitosan,
.alpha.-1,4-N-acetylchitosan (chitin), pullulan, agarose, and
alginic acid. Also, starches containing amylose are included
therein.
[0034] Of those, it is preferable to use those which can be easily
obtained as highly pure polysaccharides such as cellulose, amylose,
.beta.-1,4-xylan, .beta.-1,4-chitosan, chitin, .beta.-1,4-mannan,
inulin, and curdlan, and more preferably cellulose and amylose.
[0035] It is preferred that such a polysaccharide has a
number-average degree of polymerization (i.e., the average number
of pyranose or furanose rings per molecule) of 5 or more, and more
preferably of 10 or more . From the viewpoint of easy handling, it
is preferred that the number-average degree of polymerization is
1,000 or less, although the upper limit thereof is not particularly
limited. Particularly, it is preferred that a number-average degree
of polymerization of polysaccharide is from 50 to 400 in that the
polysaccharide or the derivative thereof is supported on the inner
wall face of the monolithic inorganic type carrier having meso
pores and a sufficient separation effect of the optical isomers is
obtained.
[0036] The polysaccharide derivative is not particularly limited so
long as it is the polysaccharide derivative which can be used for
the separation of optical isomers. Such polysaccharide derivatives
include, for example, polysaccharide derivatives which contain
optical active polysaccharide as a skeleton and where at least a
part of a hydroxyl group and an amino group which this
polysaccharide has is substituted with a functional group which
acts on an optical isomer in a sample.
[0037] The functional group is a functional group which acts on the
optical isomer in the sample containing the optical isomers which
are subject to the separation. Actions of the functional group for
the optical isomer cannot be collectively defined because a type of
the functional group is different depending on a type of the
optical isomers which are subject to the separation, but they are
not particularly limited so long as they are the actions sufficient
to perform optical resolution of the optical isomers by the
polysaccharide derivatives.
[0038] Such actions include affinitive interactions such as
hydrogen bond, .pi.-.pi. interaction and dipole-dipole interaction
of the optical isomer with the functional group, and non-affinitive
interaction such as steric hindrance. By such interactions, it is
believed that when a pair of the optical isomers gets close to the
polysaccharide derivative, a direction of the optical isomer can be
arranged without disturbing access of at least one or the optical
isomers to the polysaccharide derivative or a higher structure of
the polysaccharide derivative itself can be arranged in a shape
favorable for asymmetry recognition.
[0039] The functional group is selected depending on the type of
the optical isomers which are subject to the separation. The
functional groups include groups including aromatic groups which
are bound to the polysaccharide, for example via ester bond,
urethane bond and ether bond and which may have substituents. The
aromatic groups include heterocyclic rings and condensed rings.
Substituents which the aromatic group may have include, for
example, alkyl groups with up to about 8 carbons, halogen, amino
groups, and alkoxy groups.
[0040] A degree of substitution of the functional group is not
particularly limited. The functional group may be substituted with
part or all of the hydroxyl groups and amino groups of the
polysaccharide, for example. The degree of substitution of the
functional group is arbitrarily selected depending on various
conditions such as a type of the functional group and a type of the
polysaccharide. To be specific, a degree of substitution of the
functional group is preferably 50 to 100%, more preferably 80 to
100%. The degree of substitution of the functional group can be
measured through elemental analysis, for example.
[0041] The polysaccharide derivative can be made by known methods.
The polysaccharide derivative can be made, for example, by making a
compound capable of reacting with a hydroxyl group or amino group
contained in the polysaccharide, which includes the functional
group or becomes the functional group by a reaction with the
hydroxyl or amino group, to react with the polysaccharide by a
dehydration reaction. From the viewpoint of realizing the
separation of a broad range of optical isomers, it is particularly
preferred that the polysaccharide derivative is a carbamate
derivative of polysaccharide or an ester derivative of
polysaccharide as described in, for example, WO 95/23125 A1 and the
like.
[0042] The polysaccharide or the derivative thereof can be
supported on the monolithic inorganic type carrier by distilling
off a solvent from the monolithic inorganic type carrier filled
with a solution of polysaccharide which contains the polysaccharide
or the derivative thereof and the solvent, or replacing the solvent
with another solvent, or performing both distilling off the solvent
and replacing the solvent with the other solvent.
[0043] The term "supported" referred to herein includes a direct or
indirect physical adsorption of the monolithic inorganic type
carrier with the polysaccharide or the derivative thereof, and a
direct or indirect chemical bond of the monolithic inorganic type
carrier with the polysaccharide or the derivative thereof.
[0044] When both distilling off the solvent and replacing the
solvent with the other solvent are performed, the solvent may be
distilled off to some extent and subsequently the remaining solvent
may be replaced with the other solvent, or the solvent may be
replaced with the other solvent and subsequently the remaining
solvent may be distilled off.
[0045] As the solvent (good solvent) used for dissolution of the
polysaccharide or the derivative thereof, any organic solvents
typically used may be used so long as they can dissolve the
polysaccharide or the derivative thereof.
[0046] Examples of the solvent include: as ketone based solvents,
acetone, ethylmethylketone, and acetophenone; as ester based
solvents, ethyl acetate, methyl acetate, propyl acetate, methyl
propionate, methyl benzoate, and phenyl acetate; as ether based
solvents, tetrahydrofuran, 1,4-dioxane, diethylether, and
tert-butylmethylether; as amide based solvents,
N,N-dimethylformamide and N,N-dimethylacetamide; as imide based
solvents, N,N-dimethylimidazolidinone; as halogen based solvents,
chloroform, methylene chloride, carbon tetrachloride, and
1,2-dichloroethane; as hydrocarbon based solvents, pentane,
petroleum ether, hexane, heptane, octane, benzene, toluene, xylene,
and mesitylene; as urea based solvents, tetramethyl urea; as
alcohol based solvents, methanol, ethanol, propanol, and butanol;
as acid based solvents, acetic acid, trifluoroacetic acid, formic
acid, phenol, and catechol; and as amine based solvents,
diethylamine, triethylamine, and pyridine. These solvents may be
used alone or in mixture with multiple types.
[0047] The other solvent (poor solvent) is not particularly limited
so long as it is a solvent which replaces the solvent from the
solution of polysaccharides, but is preferably a solvent which
replaces in favor of the solvent from the solution of the
polysaccharides. As such another solvent, a solvent which is
insoluble or poorly soluble for the polysaccharide or the
derivative thereof is preferable, and can be appropriately selected
from known solvents depending on conditions such as solubility for
the polysaccharide or the derivative thereof and compatibility with
the above solvent.
[0048] Supercritical fluid can be used as a solvent which dissolves
the polysaccharide and the derivative thereof. The supercritical
fluid referred to herein is referred to fluid at a supercritical
temperature and/or pressure at which gas and liquid can coexist or
above. As this supercritical fluid, it is preferable to use carbon
dioxide, nitrogen monoxide, ammonia, sulfur dioxide, hydrogen
halide, hydrogen sulfide, methane, ethane, propane, ethylene,
propylene, halogenated hydrocarbon, and the like, and carbon
dioxide is more preferable.
[0049] An organic solvent can be added to the supercritical fluid.
As this organic solvent, it is preferable to use alcohols such as
ethanol, methanol and 2-propanol; organic acids such as acetic acid
and propionic acid; amines such as diethylamine; aldehydes such as
acetaldehyde; and ethers such as tetrahydrofuran and ethyl ether.
An addition amount of the organic solvent is preferably from 1 to
50%, more preferably from 1 to 35%, and still preferably from 1 to
20% based on the supercritical fluid.
[0050] When filling the solution of polysaccharides into the
monolithic inorganic type carrier, a concentration of the solvent
is from 1 to 100 parts by mass, preferably from 1 to 50 parts by
mass, and more preferably from 1 to 20 parts by mass based on 1
part by mass of the polysaccharide or the derivative thereof.
[0051] The monolithic inorganic type carrier having a meso pore of
the above-mentioned pore size can support a larger amount of the
polysaccharides in the meso pore compared with that of the
conventional monolithic inorganic type carrier.
[0052] Further, the monolithic inorganic type carrier having a meso
pore of the above-mentioned pore size can facilitate transfer of a
substance into and out of the meso pore compared with that of the
conventional monolithic inorganic type carrier. Thus, the
monolithic inorganic type carrier can support a sufficient amount
of the polysaccharides on a wall surface of the meso pore even when
a solution of the polysaccharides having a relatively high
viscosity is used.
[0053] The separating agent for optical isomers of the invention
can be manufactured by a method including the steps of filling the
solution of polysaccharides into the monolithic inorganic type
carrier, and at least one of distilling off the solvent from the
monolithic inorganic type carrier in which the solution is filled
and replacing the solvent with the other solvent in the monolithic
inorganic type carrier in which the solution is filled.
[0054] The step of filling the solution of polysaccharides into the
monolithic inorganic type carrier includes a method of directly
immersing the monolithic inorganic type carrier in the solution of
polysaccharides and a method of passing the solution of
polysaccharides through the monolithic inorganic type carrier with
pressure. It is preferred that the step of filling the solution of
polysaccharides into the monolithic inorganic type carrier is
performed under pressure. The pressure at that time is preferably
from 50 to 400 bar, more preferably from 50 to 200 bar. A method of
applying pressure to the solution toward the monolithic inorganic
type carrier is not particularly limited, and includes the
application of pressure by high pressure gas from a bomb or a
compressor, and the application of pressure by a pump used in
HPLC.
[0055] As the step of distilling off the solvent from the
monolithic inorganic type carrier in which the solution is filled,
an appropriate method is selected depending on the type of the
solution. Such a method includes, for example, drying under normal
pressure and drying under reduced pressure. In the invention, such
methods may be used alone or in combination.
[0056] The step of replacing the solvent with another solvent in
the monolithic inorganic type carrier in which the solution is
filled includes a method of directly immersing the monolithic
inorganic type carrier in which the solution is filled in the other
solvent and a method of passing the other solvent through the
monolithic inorganic type carrier with pressure, similarly to the
step of filling the solution of polysaccharides into the monolithic
inorganic type carrier.
[0057] When the step of filling the solution of polysaccharides
into the monolithic inorganic type carrier, and the step of at
least one of distilling off the solvent from the monolithic
inorganic type carrier in which the solution is filled and
replacing the solvent with the other solvent therein are made into
one step of supporting the polysaccharide or the derivative thereof
on the monolithic inorganic type carrier, the support of the
polysaccharide or the derivative thereof on the monolithic
inorganic type carrier may be performed at one step or may be
repeatedly performed at multiple steps, but it is preferred that it
is performed at preferably from 1 to 5 steps, more preferably from
1 to 3 steps, and still preferably 1 step.
[0058] The separating agent for optical isomers of the invention
may perform stronger fixation of the polysaccharide or the
derivative thereof on the monolithic inorganic type carrier by
forming further chemical bonds by chemical bonds between the
monolithic inorganic type carrier and the polysaccharide or the
derivative thereof, chemical bonds between the polysaccharides or
the derivatives thereof on the monolithic inorganic type carrier,
chemical bonds using a third component, reactions by photo
irradiation, irradiation of radioactive rays such as .gamma.-rays,
and irradiation of electromagnetic waves such as microwaves to the
polysaccharide or the derivative thereof on the monolithic
inorganic type carrier, radical reactions, and the like. According
to such strong fixation, when used for the separation of the
optical isomers, further improvement of availability in industries
is anticipated in the separation, analysis and fractionation etc.
of the optical isomers.
[0059] Examples of a method of fixing the polysaccharide or the
derivative thereof on the monolithic inorganic type carrier by the
chemical bond include, a method including the steps of binding the
monolithic inorganic type carrier to a binder which is fixed on the
surface of this monolithic inorganic type carrier by the chemical
bond, accreting the polysaccharide or the derivative thereof to the
monolithic inorganic type carrier to which the binder is bound, and
directly or indirectly binding the accreting polysaccharide or
derivative thereof with the binder.
[0060] This method may further include the step of introducing
substituents into the polysaccharide or the derivative thereof
which binds to the binder. In the case of including such a step, it
is possible to regulate a substitution ratio of the substituent in
the polysaccharide derivative. In the case of including the step,
it is also become possible to bind the polysaccharide to the binder
and introduce the substituent including the functional group into
the polysaccharide which binds to the binder.
[0061] The binder is not particularly limited so long as it is a
compound which is fixed to the surface of the monolithic inorganic
type carrier by the chemical bond and can further chemically bind
to the polysaccharide or the derivative thereof. Also, the binder
and the polysaccharide or the derivative thereof may be directly
bound chemically, or indirectly bound chemically via another
compound such as a crosslinking agent. The binder is appropriately
selected depending on a composition of the surface of the
monolithic inorganic type carrier, and the preferable binders
include, for example, organic silicon compounds such as silane
coupling agents.
[0062] The separation column for optical isomers of the invention
has a column tube and the separating agent for optical isomers held
in this column tube.
[0063] As the column tube, the column tube typically used can be
used depending on a use form of the column and a scale of the
column.
[0064] The separating agent for optical isomers is held in the
column tube to become a channel for fluid within the column tube. A
method of holding the separating agent for optical isomers in the
column tube is not particularly limited so long as it is the method
capable of sealing space between an inner wall face of the column
tube and a surface opposite thereto of the separating agent for
optical isomers. Known methods can be used in which the monolithic
inorganic type carrier is held in the column tube. As such a
method, for example, as disclosed in JP 2002-505005 A, it is
possible to use a method of sealing the space between the inner
wall face of the column tube and the surface opposite thereto of
the monolithic inorganic type carrier by plastic, and the like.
[0065] The separation column for optical isomers of the invention
may be manufactured by holding the separating agent for optical
isomers in the column tube, or may be manufactured by supporting
the polysaccharide or the derivative thereof by the aforementioned
steps on the monolithic inorganic type carrier of the column having
the monolithic inorganic type carrier held in the column tube to
become a channel of fluid within the column tube. The method of
supporting the polysaccharide or the derivative thereof in the
column having the monolithic inorganic type carrier is preferable
from the viewpoint of prevention of decomposition of the supported
polysaccharide or derivative thereof, ease of the manufacture, and
the like.
[0066] The separation column for optical isomers of the invention
is generally used for chromatography methods such as gas
chromatography, high-performance liquid chromatography,
supercritical chromatography, thin layer chromatography, and
capillary electrophoresis. In particular, it is preferable to apply
the separation column to the high-performance liquid chromatography
method.
[0067] Without further elaboration, it is believed that one skilled
in the art can, using the preceding description, utilize the
present invention to its fullest extent. The preferred specific
embodiments and examples are, therefore, to be construed as merely
illustrative, and not limitative of the disclosure in any way
whatsoever.
[0068] The entire disclosures of all applications, patents, and
publications cited above and below, and of corresponding
application Japanese JP2004-343683, filed Nov. 29, 2004, are hereby
incorporated by reference.
EXAMPLES
[0069] The present invention is described below in more detail
based on examples, but the invention is not limited to the
following examples.
Example 1
[0070] Production of a monolithic inorganic type porous body column
supporting amylose tris (3,5-dimethylphenylcarbamate)
[0071] (1) Synthesis of amylose
tris(3,5-dimethylphenylcarbamate)
[0072] In a nitrogen atmosphere, 10 g of amylose and 68.1 g (2.5
equivalents with respect to all of hydroxyl groups of amylose) of
3,5-dimethylphenyl isocyanate in 300 mL of dry pyridine were
stirred under heating at 100.degree. C. for 48 hours, and the whole
was poured in to 3 L of methanol. A separated solid was filtered
and collected on a glass filter, washed with methanol several
times, and dried in a vacuum. As a result, 34 g of a yellowish
white solid was obtained.
[0073] (2) Supporting of amylose tris(3,5-dimethylphenylcarbamate)
on a monolithic inorganic type porous body
[0074] Amylose tris(3,5-dimethylphenylcarbamate) synthesized in (1)
was dissolved in ethyl acetate. A concentration of the solution was
75 mg/mL.
[0075] A monolithic inorganic porous body, which has a macropore
having a pore size of 1.9 .mu.m and a meso pore having a pore size
of 25 nm formed on an inner wall surface of the macropore, was used
as a monolithic inorganic type porous body. The solution was
injected into a monolithic inorganic type porous body column from
an end part using a pump for HPLC at a pressure within a maximum
pressure of 200 bar. The monolithic inorganic type porous body
column has the monolithic inorganic porous body held in a column
tube having a length of 50 mm and an inner diameter of 4.6 mm. The
injection of the solution was stopped after the solution containing
the polysaccharide derivative was observed from a tip part of the
inorganic type porous body column (end part of the inorganic type
porous body column opposite to the end part connecting with the
pump) . Both ends of the inorganic type porous body column were
opened, and the inorganic type porous body column was dried under
normal temperature and normal pressure for about 1 week and then
dried under reduced pressure for 4 hours. A weight of the inorganic
type porous body column was measured before and after drying to
determine an end point of a drying step. As described above, an
inorganic type porous body column supporting amylose tris
(3,5-dimethylphenylcarbamate) was produced.
Example 2
[0076] An inorganic type porous body column supporting amylose tris
(3,5-dimethylphenylcarbamate) was produced in the same manner as
that in Example 1 except that a monolithic inorganic type porous
body column holding a monolithic porous body, which has a macropore
having a pore size of 4.5 .mu.m and a meso pore having a pore size
of 23 nm, in the column tube, was used in place of the monolithic
inorganic type porous body column used in Example 1.
Example 3
[0077] An inorganic type porous body column supporting amylose tris
(3,5-dimethylphenylcarbamate) was produced in the same manner as
that in Example 1 except that a monolithic inorganic type porous
body column holding a monolithic porous body, which has a macropore
having a pore size of 6.0 .mu.m and a meso pore having a pore size
of 24.4 nm, in the column tube, was used in place of the monolithic
inorganic type porous body column used in Example 1.
Comparative Example 1
[0078] An inorganic type porous body column supporting amylose tris
(3,5-dimethylphenylcarbamate) was produced in the same manner as
that in Example 1 except that a monolithic inorganic type porous
body column holding a monolithic porous body, which has a macropore
having a pore size of 1.8 .mu.m and a meso pore having a pore size
of 10.9 nm, in the column tube, was used in place of the monolithic
inorganic type porous body column used in Example 1.
Comparative Example 2
[0079] An inorganic type porous body column supporting amylose tris
(3,5-dimethylphenylcarbamate) was produced in the same manner as
that in Example 1 except that a monolithic inorganic type porous
body column holding a monolithic porous body, which has a macropore
having a pore size of 4.5 .mu.m and a meso pore having a pore size
of 10.2 nm, in the column tube, was used in place of the monolithic
inorganic type porous body column used in Example 1.
Comparative Example 3
[0080] An inorganic type porous body column supporting amylose tris
(3,5-dimethylphenylcarbamate) was produced in the same manner as
that in Example 1 except that a monolithic inorganic type porous
body column holding a monolithic porous body, which has a macropore
having a pore size of 5.74 .mu.m and a meso pore having a pore size
of 10.0 nm, in the column tube, was used in place of the monolithic
inorganic type porous body column used in Example 1.
<Measurement and Evaluation>
[0081] The inorganic type porous body columns produced in Examples
1 to 3 and the inorganic type porous body columns produced in
Comparative Examples 1 to 3 were each used for separation of
optical isomers shown in Table 1 by liquid chromatography. A
retention time of each of the optical isomers in each of the
columns was measured, to thereby determine a separation factor a
and the number of theoretical plates for each of the columns. Table
1 shows the separation factor .alpha., and Table 2 shows the number
of theoretical plates.
TABLE-US-00001 TABLE 1 Separation factor .alpha. (-) Racemic
Comparative Comparative Comparative modification Structural formula
Example 1 Example 2 Example 3 example 1 example 2 example 3 t-SO
##STR00001## 3.27 3.40 3.28 3.00 2.95 2.80 Bz ##STR00002## 1.32
1.29 1.30 1.24 1.21 1.17 TR-base ##STR00003## 1.29 1.28 1.28 1.14
1.12 1.00 TFAE ##STR00004## 1.28 1.21 1.21 1.11 1.00 1.00 TrOH
##STR00005## 2.28 2.25 2.28 2.28 2.19 2.22 Biph ##STR00006## 2.29
2.33 2.30 2.24 2.26 2.23
TABLE-US-00002 TABLE 2 Amount of supported Pore size of Pore size
of Number of theoretical plates N (--) polymer macropore meso pore
t-SO Biph TrOH (mg) (.mu.m) (nm) N.sub.1 N.sub.2 N.sub.1 N.sub.2
N.sub.1 N.sub.2 Example 1 110.3 1.9 25 2491 1738 1234 1077 1255
1137 Example 2 105.2 4.5 23 1616 1119 565 439 414 357 Example 3
104.8 6.0 24.4 1020 476 285 186 189 145 Comparative 116.7 1.8 10.9
2063 1471 1051 763 885 752 example 1 Comparative 107.4 4.5 10.2
1178 688 414 301 263 233 example 2 Comparative 100.1 5.74 10.0 654
287 170 111 109 77 example 3
[0082] The separation factor .alpha. in Table 1 is determined by
the following equation (1). In the equation (1), k.sub.1'
represents a capacity ratio of an optical isomer eluted faster
among the separated optical isomers, and k.sub.2' represents a
capacity ratio of an optical isomer eluted slower among the
separated optical isomers.
[Formula 1]
separation factor (.alpha.)=k.sub.2'/k.sub.1' (1)
[0083] The capacity ratio k.sub.r' is determined by the following
equation (2). In the equation (2), t.sub.r represents a retention
time of an optical isomer, and t.sub.0 represents an elution time
of tri-tert-butylbenzene.
[Formula 2]
capacity ratio (k.sub.r')=(t.sub.r-t.sub.0)/t.sub.0 (2)
[0084] The number of theoretical plates N in Table 2 is determined
by the following equation (3). In the equation (3), W.sub.0.5
represents a peak width at half height. The peak width W refers to
a distance (time) between cross points of tangent lines drawn at
inflection points of the peak on both sides of the peak, and a base
line.
[Formula 3]
number of theoretical plates
(N)=5.5.times.(t.sub.r/W.sub.0.5).sup.2 (3)
[0085] An amount of the polymer supported in Table 2 refers to a
difference (mg) between a mass of the inorganic type porous body
column having a polymer supported thereon and a mass of the
inorganic type porous body column not having the polymer supported
thereon.
[0086] Tables 1 and 2 clearly show that the inorganic type porous
body column produced in each of Examples exhibits better
performance as a separation column for optical isomers compared
with the inorganic type porous body column produced in each of
Comparative Examples.
* * * * *