U.S. patent application number 10/620513 was filed with the patent office on 2004-05-06 for method and kit for removing aldehyde-based stains.
Invention is credited to Feldman, Les, Hui, Henry, Zhu, Peter.
Application Number | 20040084060 10/620513 |
Document ID | / |
Family ID | 26983198 |
Filed Date | 2004-05-06 |
United States Patent
Application |
20040084060 |
Kind Code |
A1 |
Zhu, Peter ; et al. |
May 6, 2004 |
Method and kit for removing aldehyde-based stains
Abstract
A method and kit are disclosed for removing or alleviating the
severity or intensity of stains from aldehyde-based sterilizing
solutions through the use of reducing agents. This invention is
effective even for porous surfaces such as filter paper and porous
nylon films as well as for smooth surfaces such as glass, aluminum,
copper, brass and stainless steel. Also, the invention may be used
in a variety of formats such as a kit useful for making or using
solutions or gels to treat the aldehyde-based stained surfaces of,
for example, medical devices, hospital bench or table tops,
hospital floors and skin (if in appropriate pH range), etc.
Inventors: |
Zhu, Peter; (Irvine, CA)
; Hui, Henry; (Laguna Niguel, CA) ; Feldman,
Les; (Calabasas Hills, CA) |
Correspondence
Address: |
PHILIP S. JOHNSON
JOHNSON & JOHNSON
ONE JOHNSON & JOHNSON PLAZA
NEW BRUNSWICK
NJ
08933-7003
US
|
Family ID: |
26983198 |
Appl. No.: |
10/620513 |
Filed: |
July 16, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10620513 |
Jul 16, 2003 |
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09747230 |
Dec 22, 2000 |
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6670520 |
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09747230 |
Dec 22, 2000 |
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09321964 |
May 28, 1999 |
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6399850 |
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Current U.S.
Class: |
134/2 ; 134/3;
134/40; 134/41; 510/130; 510/214; 510/217; 510/276 |
Current CPC
Class: |
C07C 45/78 20130101;
A62D 2101/28 20130101; A61L 2/16 20130101; A62D 3/30 20130101; C07C
227/18 20130101; C07C 227/18 20130101; C07C 229/16 20130101 |
Class at
Publication: |
134/002 ;
134/003; 134/040; 134/041; 510/130; 510/214; 510/217; 510/276 |
International
Class: |
C23G 001/00 |
Claims
What is claimed is:
1. A method for removing or lessening the severity of
aldehyde-based stains comprising the steps of: a) providing an
aldehyde-based stain on a surface or in a material; and b) applying
a reducing agent to the stained surface or material.
2. The method of claims 1, wherein the reducing agent is selected
from the group consisting of LiAlH.sub.4, NaBH.sub.4, NaCNBH.sub.3,
Na-Ethyl alcohol, and hydrogen/catalyst and mixtures thereof.
3. The method of claim 1, wherein the aldehyde-based stain
comprises an imine formed from an aldehyde and a chemical
containing amino group.
4. The method of claim 3, wherein the aldehyde comprises a
germicide.
5. The method of claim 3, wherein the aldehyde comprises one or
more (CHO) functional group.
6. The method of claim 3, wherein the aldehyde comprises a
dialdehyde.
7. The method of claim 3, wherein the aldehyde is selected from the
group consisting of ortho-phthalaldehyde, glutaraldehyde,
formaldehyde and mixtures thereof.
8. The method of claim 3, wherein the chemical is selected from the
group consisting of alkyl amine, aryl amine, polymer amine,
protein, peptide, amino acid, and any combination thereof.
9. The method of claim 1, wherein the surface or material is
selected from the group consisting of a bench top, floor, medical
device, drape, gown, dressing and human skin.
10. A kit for removing or lessening the severity of aldehyde-based
stains comprising: a) a source of reducing agent; and b)
instructions regarding the proper amount of reducing agent to be
combined with a solvent or a gel in order to provide a solution or
a suspension of effective strength to remove or lessen
aldehyde-based stains.
11. The kit of claim 10, further comprising a container within
which to combine the reducing agent and solvent.
12. The kit of claim 10 or 11, wherein the instructions require use
of a solvent selected from the group consisting of water, alcohol,
acid, gel and mixtures thereof.
13. The kit of claim 12, wherein the acid includes organic and
inorganic compounds with at least one active hydrogen.
14. The kit of claim 10, wherein the reducing agent is selected
from the group consisting of LiAlH.sub.4, NaBH4, NaCNBH.sub.3,
Na-Ethyl alcohol, and hydrogen/catalyst and mixtures thereof.
15. The kit of claim 11 wherein the container is a spray
bottle.
16. The kit of claim 11 wherein the container comprises a
dropper.
17. The kit of claim 11 wherein the aldehyde-based stain comprises
an imine formed from an aldehyde and a chemical containing amino
group.
Description
[0001] This patent application is a continuation-in-part of
co-pending and commonly assigned patent application U.S. Ser. No.
09/747,230, filed Dec. 22, 2000 entitled "Reductive Amination for
Aldehyde Neutralization Related Applications" which is a
continuation-in-part of co-pending and commonly assigned patent
application U.S. Ser. No. 09/321,964, filed May 28, 1999 entitled
"Aldehyde Neutralizer", the disclosures of which are hereby
incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to a method and kit for removing or
lessening the severity of aldehyde-based stains, in particular,
stains formed by reaction of aldehydes with amino-containing
compounds.
[0004] 2. Description of Related Art
[0005] Aldehyde-based germicides are commonly used in the
healthcare facilities to disinfect and sterilize medical devices.
One related problem associated with the use of aldehyde-based
germicides such as formaldehyde, glutaraldehyde and
ortho-phthalaldehyde (OPA) that have been reacted with
amino-containing compounds is that the surfaces and/or the material
that come into contact with the neutralized aldehyde become
stained. Also residual aldehyde on surfaces or absorbed into the
materials such as plastic will cause staining later when exposed to
amino-containing compounds. This is a problem in a hospital
environment when sterile surfaces and/or materials that are stained
can cause concern that the devices are not sterile. Such surfaces
include but or not limited to bench tops, floor surfaces, medical
devices (metal or plastic) and human skin. Some OPA related stains
are the results of formation of Schiff's bases which are dark in
color. Although the staining in the hospital environment is very
problematic, there are no good measures to solve the problem at
present. This invention offers solutions to this problem.
SUMMARY OF THE INVENTION
[0006] In one embodiment the invention relates to a method for
removing or lessening the severity of aldehyde-based stains on
surfaces or in materials comprising the steps of:
[0007] a) providing an aldehyde-based stain on a surface or in a
material; and
[0008] b) applying a reducing agent to the stained surface or
material.
[0009] In another embodiment, the invention relates to a kit
comprising:
[0010] a) a source of reducing agent; and
[0011] b) instructions regarding the proper amount of reducing
agent to be combined with a solvent or a gel in order to provide a
solution or a suspension of effective strength to remove or lessen
aldehyde-based stains.
[0012] Among the advantages of the invention is removal of
aldehyde-based stains to no stain or at least to a stain of
lessened severity or intensity. This invention is effective even
for porous surfaces such as filter paper and porous nylon films as
well as for smooth surfaces such as glass, aluminum, copper, brass
and stainless steel. Also, the invention may be used in a variety
of formats such as a kit useful for making or using solutions or
gels.
[0013] Additional features, embodiments, and benefits of the
invention will be evident in view of the detailed description
presented below.
DETAILED DESCRIPTION OF THE INVENTION
[0014] Commonly assigned and co-pending patent application U.S.
Ser. No. 09/321,964 discloses the neutralization of aldehdye with
amino acid. The neutralized aldehyde product can be formed by
reacting an amino group from an amino acid or proteins with an
aldehyde group of aldehydes to produce N-substituted adducts
(imines or Schiff's bases) as shown below. 1
[0015] There are a variety of amino acids that are useful in
neutralizing aldehydes. These amino acids include:
[0016] (1) Amino acids with apolar R groups (e.g., alanine,
proline, amino-caproic acid, phenylalanine, tryptophan and
methionine);
[0017] (2) Amino acids with polar R groups (e.g., glycine, serine,
cysteine, tyrosine, and glutamine);
[0018] (3) Amino acids with charged R groups (e.g., aspartic acid,
glutamic acid, lysine, arginine, and histidine); and,
[0019] (4) Peptides/polypeptides formed by any number or any type
of amino acids and proteins.
[0020] The aldehyde can be a germicide that includes formaldehyde,
glutaraldehyde, and OPA.
[0021] While the discovery of forming neutralized aldehydes for
lessening the toxic effects of disposing of aldehyde treated waste
was a major advance, resulting colored products (and hence
susceptibility to forming stains) and the possibility of the
neutralized aldehydes in reforming aldehydes under acidic
conditions posed a problem in effectively maintaining nonhazardous
waste because of the toxic effects of unneutralized aldehyde. The
reversible reaction is depicted below for treatment of
glutaraldehyde (1) and o-phthaladehyde (4) with the amino acid,
glycine (2) to the neutralized products, (3) and (5), respectively:
2
[0022] Reversible Schiff s Base Formation between Aldehydes and
Glycine
[0023] Commonly assigned and co-pending patent application U.S.
Ser. No. 09/747,230 discloses that the treatment of the neutralized
products with a reducing agent to form amino acids do not cause
them to revert back to unneutralized aldehyde. This reaction is
depicted below for saturated moieties (6) and (7) as for the
reduction of Schiff's bases (3) and (5) treated with the reducing
agent sodium borohydride, NaBH.sub.4: 3
[0024] Room Temperature and Easy Conversion of Schiff's Bases 3 and
5 to Light-colored Amino Acids 6 and 7
[0025] Being simple amino acids compounds (6) and (7) would be
expected to be biodegradable and thus have significant benefit for
the environment. This appears apparent by examination of the
resemblance of the structures (6) and (7) with the 5 natural
essential amino acid proline, (8). The corresponding resemblance is
depicted with bold-faced highlighting of compounds (6) and (7)
shown below: 4
[0026] The Resemblance of Natural Amino Acid 8 with Amino Acid 6
and 7
[0027] In contrast, Schiff's base (3) and (5) do not have the above
characteristics and are likely very different compounds. One
skilled in the art would suspect Schiff's bases to be harder to
degrade in nature than the corresponding amino acids. For example,
a piece of animal skin could decay in a few days in the wild while
men's belts, made from animal skin too, could take many years. This
is because the belt (leather) has undergone a tanning process.
Tanning processes often employ the glutaraldehyde derivatives, such
as depicted as structures (9) and (10) below, to cross-link
proteins (Ref. a. Fein, M. L. and Filachione, E. M., "Tanning
studies with aldehydes", J. Am. Leather Chem. Assoc., 52, 17, 1957;
b. Weligsberger, L. and Sadlier, C., "New developments in tanning
with aldehydes", J. Am. Leather Chem. Assoc., 52, 2, 1957; c.
Hopwood, D., "Comparison of crosslinking abilities of
glutaraldehyde, formaldehyde, and .alpha.-hydroxyadipaldehyde with
bovine serum albumin and casein", Histochemie, 17, 151, 1969). It
is well known that OPA has very similar protein cross-liking
properties. 5
[0028] The Tanning Agents (Protein Cross-linkers)
[0029] The conditions for Schiff's base reduction (and hence the
removal or lessening of stains) is easy and convenient. Normally,
it involves the mixing of the reducing agent, such as NaBH.sub.4,
and the imine, such as neutralized aldehyde, in a protonic solvent,
such as water, ethanol, methanol, acid, or gel at room temperature.
The acid may be organic or inorganic having active hydrogens. Due
to the formation of colorless or light-colored products between the
reducing agent and the imine, it is found that the reducing agent
is a good chemical for removing the stains. The reducing agent can
be applied to the stains by washing, spraying or dropping a
solution containing the reducing agent onto the stained surface, by
soaking the stained material in the solution containing the
reducing agent, or by rubbing a gel or lotion comprising the
reducing agent onto the stained surface or into the stained
material.
[0030] The imine can be reduced by many reducing agents, such as
LiAlH.sub.4 (lithium aluminum hydride), NaBH.sub.4 (sodium
borohydride), NaCNBH.sub.3 (sodium cyanoborohydride), Na--EtOH
(metallic sodium in ethyl alcohol), and H.sub.2/catalyst (hydrogen
with a catalyst). A preferred reducing agent is NaBH.sub.4.
EXAMPLES
[0031] In the following examples, all percentages (%) referring to
solutions are expressed as wt/vol, except in the case of Cidex.RTM.
OPA where the percentages is expressed as wt/wt. The pH of the 1%
aqueous sodium borohydride solution used in the following examples
was measured to be 10.8.
Example 1
[0032] (a) Cidex.RTM. OPA solution (0.55%, 1.0 mL) and glycine
solution (1%, 1.0 mL) were mixed in a vial for 2 minutes and a
green color developed and darkened quickly.
[0033] (b) Sodium borohydride solution (1%, 1.0 mL) was added,
shaken and mixed to the solution. The solution gradually became
yellow and never darkened. The solution never turned black. Thus,
the severity or intensity of the staining solution of (a) was
lessened by the reducing agent sodium borohydride.
Example 2
[0034] (a) Cidex.RTM. OPA solution (0.55%, 0.05 mL) was applied to
porous nylon film for about 10 minutes at room temperature (until
dry). Glycine (1%, 0.05 mL) was applied on the top of the
Cidex.RTM. OPA spot. In about 10 minutes, the spot showed a
green-black color.
[0035] (b) Sodium borohydride solution (1%, 0.15 mL) was applied
onto the top of the green-black spot. The green-black spot was
de-stained immediately to turn to a much lighter color (yellowish
brown).
Example 3
[0036] (a) Cidex.RTM. OPA (0.55%, 0.05 mL) was applied on porous
nylon film and dried in about 2 hours at room temperature. Glycine
(1%, 0.05 mL) was added on the top of the Cidex.RTM. OPA spot and
after 2 minutes, the spot became green-black.
[0037] (b) The stained nylon film was then soaked in sodium
borohydride solution (1%, 10 mL) for 10 minutes, the green-black
spot changed to a light-yellow spot. The color was noted to
continue to fade with continued soaking.
[0038] (c) For comparison, the same experiment was repeated.
However, instead of soaking in the sodium borohydride solution, the
film was soaked in the water for 10 minutes. No reduction of the
green-black color was observed. In fact, the greenblack color never
faded by soaking in water for 2 days.
Example 4
[0039] (a) Cidex.RTM. OPA solution (0.55%, 0.05 mL) was applied to
filter paper ("Fisherbrand", qualitative P2, porosity: fine) and
dried at room temperature for two hours. Glycine (1%, 0.05 mL) was
added on the top of the Cidex.RTM. OPA spot and after about 2
minutes, the spot became a green-black color.
[0040] (b) The stained filter paper was soaked in sodium
borohydride solution (1%, 10 mL) for 5 minutes when the green-black
spot changed to very light-yellow spot. The spot became colorless
when the soaking continued for 2 hours.
[0041] (c) For comparison, the same experiment was repeated.
However, instead of soaking in sodium borohydride solution, the
filter paper was soaked in the water for 10 minutes. No reduction
of the green-black color was observed. In fact, the green-black
color never faded even after soaking in water for 2 days.
Example 5
[0042] (a) Cidex.RTM. OPA solution (0.55%, 0.05 mL) was applied to
two (2) aluminum coupons (1.times.1 inches) and glycine (1%, 0.05
mL) was added on the top of the Cidex.RTM. OPA spots. The aluminum
coupons were then heated at 80.degree. C. for 2 hours. A
brown-black residual spot formed on each coupon.
[0043] (b) One coupon was then soaked in sodium borohydride
solution (1%, 10 mL) at room temperature. Surprisingly, the black
residue on the aluminum surface disappeared instantly (less than 3
seconds). The solution became clear yellow. The surprisingly good
result on the metal surface was not expected.
[0044] (c) The other coupon, the control coupon, was soaked in 10
mL water, where most of the brown-black residue dissolved
gradually. However, there was still residue left on the coupon
after 3 hours. The solution became dark green with black residue
deposit on the bottom of the vial.
Example 6
[0045] Example 5 was duplicated with brass coupons with even better
results. The brown-black residue came off instantly while that on
the control coupon came off only partially and the remainder came
off very slowly and it remained even after soaking in water for 2
days.
Example 7
[0046] Example 5 was duplicated with copper coupons. The same
excellent result was observed as in Example 5.
Example 8
[0047] Example 5 was duplicated with stainless steel surfaces. Thee
same excellent result was observed as in Example 5.
Example 9
[0048] (a) Cidex.RTM. OPA solution (0.55%, 0.05 mL) was added into
a scintillation vial and glycine (1%, 0.05 mL) was added and mixed.
The solution was heated at 80.degree. C. for 1 hour and a black
residue was left on the bottom of the vial.
[0049] (b) Sodium borohydride solution (1%, 2 mL) was then added
and the black residue was dissolved instantly to give a clear
yellowish-brown solution (no green or black color).
[0050] (c) On the other hand, for the control experiment, the same
procedure as above was followed except water (instead of sodium
borohydride solution) was added to the vial. The black residue came
off the glass wall after shaking and most of the residues remain
suspended in the solution for 2 days. The solution appeared to be
dark-green in color.
Example 10
[0051] Examples 5-9 were repeated. In this case, fresh sodium
borohydride versus aged solution (1 day old) was compared. All gave
good results. All the black Schiff's base residue on different
metal coupons came off instantly after exposing to the 1% sodium
borohydride solution.
Example 11
[0052] (a) Silicone tubing (OD=0.60 cm, wall thickness=2 mm) was
soaked in the Cidex.RTM. OPA solution for seven days, washed with
detergent, rinsed with water and then soaked in an amino solution
to pick up the homogenous dark stains.
[0053] (b) The above silicone tubing (1.0 cm in length) was soaked
in sodium borohydride (1%, 5 mL) for 2 hours, the majority of the
color disappeared.
[0054] (c) Comparatively, the tubing soaked in water in place of
the sodium borohydride did not fade in 1 month.
[0055] Therefore, based on Examples 1-11, it would be appreciated
by those skilled in the art that depending on the nature of the
material, the time or the efficiency to remove the stain may vary.
Metal may require less time than non-metal, and absorbent or porous
materials may require longer time than non-absorbent or non-porous
materials.
Example 12
[0056] Example 11 was duplicated with a slight modification.
Instead of water, 50% ethanol in water was used as the solvent. In
this case, compared to the control (water as solvent), the
de-staining rate is somewhat faster.
Example 13
[0057] (a) Procedure: Cidex.RTM. OPA solution (0.55%, 10 mL) was
mixed with glycine (1%, 10 mL). The mixed solution separately was
applied to brass and aluminum coupons (20 .mu.L mixed solution for
each stain). The coupons were then heated at 80.degree. C. for 2
hours. Brown-black residual spots formed.
[0058] (b) Each coupon (with one stain spot on it) was soaked in
aqueous NaBH.sub.4 solutions of varying concentrations as shown in
Table 1. The time it took to remove the stain spot completely was
recorded in Table 1.
1TABLE 1 Effect of concentration on the Time (in seconds) required
to remove Schiff based stains NaBH.sub.4 Concentration 1% 0.5%
0.25% 0.125% 0.0625% Schiff' base stain 2" .+-. 0.5 3" .+-. 1 4"
.+-. 1 15" .+-. 5 26" .+-. 7 on brass Schiff' base stain 3" .+-.
0.5 3" .+-. 1 4" .+-. 1 12".+-. 5 22" .+-. 7 on aluminum
[0059] Thus aqueous NaBH.sub.4 solutions of various concentrations
are quite effective for rapid removal of Schiff-based stains
Example 14
[0060] Reduction to product formats.
[0061] The following solutions could be used for soaking medical
devices or wiping, or spraying medical surfaces or bench tops,
floor surfaces etc. Since the pH is around 10.8, normal care should
be taken (gloves/ventilation).
[0062] Reduction to product format--(14-1):
[0063] Sodium borohydride powder (0.5-5 g) is packed in bottles.
Cap well. Add water before use (to dilute to near 1%).
[0064] Reduction to product format--(14-2):
[0065] Sodium borohydride powder (0.5-5 g) is packed in bottles.
Cap well. Add mixture of water or an alcohol (ethanol, or
isopropanol or methanol or mixed alcohol) before use (to dilute to
near 1%).
[0066] Reduction to product format--(14-3):
[0067] Sodium borohydride powder (0.5-5 g) and an amino acid (such
as glycine, lysine etc) are packed in bottles as dry powder. Cap
well. Add mixture of water or an alcohol (ethanol, or isopropanol
or methanol or mixed alcohol) before use (to dilute to near
1%).
[0068] Reduction to product format--(14-4):
[0069] A container in the form of a spray bottle or bottle with a
dropper may be used for formats 14-1 to 14-3.
[0070] Reduction to product format--(14-5):
[0071] Instead of using bottle container, the sodium borohydride
powder could be packed into aluminum bags or other types of bags to
reduce product sizes.
[0072] Reduction to product format--(14-6):
[0073] Nitrogen or another inert gas could be filled into the
packaging formats in order to increase shelf life.
[0074] Reduction to product format--(14-7):
[0075] Desiccators could be used for the above packaging formats in
order to increase shelf life.
[0076] Reduction to product format--(14-8):
[0077] Other reducing agents of similar nature could be used, such
as sodium cyanoborohydride, metallic sodium in ethyl alcohol, and
H.sub.2/catalyst.
[0078] The invention is well suited for formation of kits wherein
the dry powder form of the reducing agent may be combined with a
solvent such as water, alcohol, or mixtures thereof, to form a
solution of desired concentration and pH. Instructions within the
kit would provide guidance regarding the proper amount of reducing
agent to be combined with the solvent in order to provide a
solution of effective strength to remove or lessen aldehyde-based
stains. The resulting solutions may be used as soaking, wiping, or
spraying solutions to treat the stained surfaces, for example, of
medical devices, bench or table tops, floors and skin (if in
appropriate pH range), etc.
[0079] In the preceding detailed description, the invention is
described with reference to specific embodiments thereof. It will,
however, be evident that various modifications and changes may be
made thereto without departing from the broader spirit and scope of
the invention as set forth in the claims. The specification and
drawings are, accordingly, to be regarded in an illustrative rather
than a restrictive sense.
* * * * *