U.S. patent application number 14/135958 was filed with the patent office on 2014-04-24 for enhanced activity hydrogen peroxide disinfectant.
This patent application is currently assigned to Virox Technologies Inc.. The applicant listed for this patent is Virox Technologies Inc.. Invention is credited to Navid OMIDBAKHSH OMIDBAKHSH, Jose A. Ramirez.
Application Number | 20140113001 14/135958 |
Document ID | / |
Family ID | 27734556 |
Filed Date | 2014-04-24 |
United States Patent
Application |
20140113001 |
Kind Code |
A1 |
Ramirez; Jose A. ; et
al. |
April 24, 2014 |
ENHANCED ACTIVITY HYDROGEN PEROXIDE DISINFECTANT
Abstract
An aqueous disinfecting solution having a pH of from about 0.5
to about 6 and consisting essentially of: (i) hydrogen peroxide in
a concentration of from about 0.05% w/w to about 8% w/w; (ii) at
least one anionic surfactant chosen from C8 to C16 alkyl aryl
sulfonic acids and alkali metal, ammonium, ethanolamine, calcium
and magnesium salts thereof; sulfonated C12 to C22 carboxylic acids
and alkali metal, ammonium, calcium and magnesium salts thereof; C6
to C22 alkyl diphenyl oxide sulfonic acids and alkali metal,
ammonium, calcium and magnesium salts thereof; naphthalene sulfonic
acids and alkali metal, ammonium, calcium and magnesium salts
thereof; C8 to C22 alkyl sulfonic acids and alkali metal, ammonium,
calcium and magnesium salts thereof; alkali metal, ammonium,
calcium and magnesium C8 to C18 alkyl sulfates; alkyl or alkenyl
esters or diesters of sulfosuccinic acids in which the alkyl or
alkenyl groups independently contain from six to eighteen carbon
atoms and alkali metal, ammonium, calcium and magnesium salts
thereof; in a concentration of from about 0.02% w/w to about 8%
w/w; and (iii) benzyl alcohol in a concentration of from about 0.1%
w/w to about 10% w/w. Optionally, the solution may contain (iv) at
least one carboxylic acid chosen from monocarboxylic acids and
polycarboxylic acids, in a concentration of from about 0.05% w/w to
about 4% % w/w. The solution may also contain an alcohol comprising
one to six carbon atoms in a concentration of from about 0.1% w/w
to about 10% w/w % w/w of the solution.
Inventors: |
Ramirez; Jose A.; (Vernon
Hills, IL) ; OMIDBAKHSH; Navid OMIDBAKHSH; (Fairfax,
VA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Virox Technologies Inc. |
Oakville |
|
CA |
|
|
Assignee: |
Virox Technologies Inc.
Oakville
CA
|
Family ID: |
27734556 |
Appl. No.: |
14/135958 |
Filed: |
December 20, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13426191 |
Mar 21, 2012 |
8637085 |
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14135958 |
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12557972 |
Sep 11, 2009 |
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13426191 |
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11518188 |
Sep 11, 2006 |
7632523 |
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12557972 |
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10364348 |
Feb 12, 2003 |
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11518188 |
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60355753 |
Feb 12, 2002 |
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Current U.S.
Class: |
424/616 |
Current CPC
Class: |
A01N 25/30 20130101;
A61K 8/466 20130101; A01N 59/00 20130101; A61Q 19/00 20130101; C11D
3/48 20130101; A61P 31/00 20180101; A01N 59/00 20130101; A61P 31/04
20180101; A01N 59/00 20130101; C11D 3/43 20130101; Y10S 424/06
20130101; A01N 2300/00 20130101; A01N 37/02 20130101; Y10S 514/97
20130101; A01N 25/30 20130101; A01N 25/30 20130101; A01N 25/30
20130101; A01N 37/36 20130101; A01N 25/02 20130101; C11D 3/3947
20130101; A01N 59/00 20130101; A61K 8/22 20130101; C11D 3/3454
20130101; C11D 3/2075 20130101; A01N 59/00 20130101; A61Q 19/007
20130101 |
Class at
Publication: |
424/616 |
International
Class: |
A01N 25/30 20060101
A01N025/30; A61K 8/46 20060101 A61K008/46; A61Q 19/00 20060101
A61Q019/00; A01N 59/00 20060101 A01N059/00; A61K 8/22 20060101
A61K008/22 |
Claims
1. An aqueous disinfecting solution having a pH of from about 0.5
to about 6 and consisting essentially of: i) hydrogen peroxide in a
concentration of from about 0.05% w/w to about 8% w/w; ii) at least
one anionic surfactant chosen from C8 to C16 alkyl aryl sulfonic
acids and alkali metal, ammonium, ethanolamine, calcium and
magnesium salts thereof; sulfonated C12 to C22 carboxylic acids and
alkali metal, ammonium, calcium and magnesium salts thereof; C6 to
C22 alkyl diphenyl oxide sulfonic acids and alkali metal, ammonium,
calcium and magnesium salts thereof; naphthalene sulfonic acids and
alkali metal, ammonium, calcium and magnesium salts thereof; C8 to
C22 alkyl sulfonic acids and alkali metal, ammonium, calcium and
magnesium salts thereof; alkali metal, ammonium, calcium and
magnesium C8 to C18 alkyl sulfates; alkyl or alkenyl esters or
diesters of sulfosuccinic acids in which the alkyl or alkenyl
groups independently contain from six to eighteen carbon atoms and
alkali metal, ammonium, calcium and magnesium salts thereof; in a
concentration of from about 0.02% w/w to about 8% w/w; and iii)
benzyl alcohol in a concentration of from about 0.1% w/w to about
10% w/w.
2. A solution according to claim 1 wherein the hydrogen peroxide is
present in a concentration of up to about 2.5% w/w.
3. A solution according to claim 1 wherein the hydrogen peroxide is
present in a concentration of from about 0.45% w/w.
4. A solution according to claim 1 wherein the anionic surfactant
is present in a concentration of up to about 6% w/w.
5. A solution according to claim 1 wherein the anionic surfactant
is present in a concentration of up to about 4% w/w.
6. A solution according to claim 1 wherein the anionic surfactant
is present in a concentration of up to about 2% w/w.
7. A solution according to claim 1 having a pH of up to about
4.5.
8. A solution according to claim 1 having a pH of up to about
2.
9. A concentrated aqueous hydrogen peroxide solution which can be
diluted with water to produce a solution according to claim 1.
10. An aqueous disinfecting solution having a pH of from about 0.5
to about 6 and consisting essentially of: i) hydrogen peroxide in a
concentration of from about 0.05% w/w to about 8% w/w; ii) at least
one anionic surfactant chosen from C8 to C16 alkyl aryl sulfonic
acids and alkali metal, ammonium, ethanolamine, calcium and
magnesium salts thereof; sulfonated C12 to C22 carboxylic acids and
alkali metal, ammonium, calcium and magnesium salts thereof; C6 to
C22 alkyl diphenyl oxide sulfonic acids and alkali metal, ammonium,
calcium and magnesium salts thereof; naphthalene sulfonic acids and
alkali metal, ammonium, calcium and magnesium salts thereof; C8 to
C22 alkyl sulfonic acids and alkali metal, ammonium, calcium and
magnesium salts thereof; alkali metal, ammonium, calcium and
magnesium C8 to C18 alkyl sulfates; alkyl or alkenyl esters or
diesters of sulfosuccinic acids in which the alkyl or alkenyl
groups independently contain from six to eighteen carbon atoms and
alkali metal, ammonium, calcium and magnesium salts thereof; in a
concentration of from about 0.02% w/w to about 8% w/w; iii) benzyl
alcohol in a concentration of from about 0.1% w/w to about 10% w/w;
and iv) at least one carboxylic acid chosen from monocarboxylic
acids and polycarboxylic acids in a concentration of from about
0.05% w/w to about 4% w/w.
11. A solution according to claim 10 wherein said at least one
carboxylic acid is present in a concentration of from about 2% w/w
to about 5% w/w.
12. An aqueous disinfecting solution having a pH of from about 0.5
to about 6 and consisting essentially of: i) hydrogen peroxide in a
concentration of from about 0.05% w/w to about 8% w/w; ii) at least
one anionic surfactant chosen from C8 to C16 alkyl aryl sulfonic
acids and alkali metal, ammonium, ethanolamine, calcium and
magnesium salts thereof; sulfonated C12 to C22 carboxylic acids and
alkali metal, ammonium, calcium and magnesium salts thereof; C6 to
C22 alkyl diphenyl oxide sulfonic acids and alkali metal, ammonium,
calcium and magnesium salts thereof; naphthalene sulfonic acids and
alkali metal, ammonium, calcium and magnesium salts thereof; C8 to
C22 alkyl sulfonic acids and alkali metal, ammonium, calcium and
magnesium salts thereof; alkali metal, ammonium, calcium and
magnesium C8 to C18 alkyl sulfates; alkyl or alkenyl esters or
diesters of sulfosuccinic acids in which the alkyl or alkenyl
groups independently contain from six to eighteen carbon atoms and
alkali metal, ammonium, calcium and magnesium salts thereof; in a
concentration of from about 0.02% w/w to about 8% w/w; iii) benzyl
alcohol in a concentration of from about 0.1% w/w to about 10% w/w;
and iv) an alcohol comprising one to six carbon atoms, in a
concentration of from about 0.1% w/w to about 10% w/w.
13. A solution according to claim 1 consisting essentially of at
least one ingredient selected from the group consisting of hydrogen
peroxide stabilizers, foam generating or stabilizing ingredients,
emulsifiers, hydrotropes, detergents, corrosion inhibitors,
moisturizing, skin conditioning agents and thickening agents, in a
total concentration of up to 10% w/w.
14. A solution according to claim 13 wherein the hydrogen peroxide
stabilizer is selected from the group consisting of
1-hydroxyethylidene-1,1-diphosphonic acid, amino tri(methylene
phosphonic acid), 2-hydroxyethylimino tri(methylene phosphonic
acid), ethylene diamine tetra(methylene phosphonic acid),
phosphoric acid, and sodium tripolyphosphate.
15. A solution according to claim 13 wherein the emulsifier and
detergent are non-ionic alkylated alkoxylate surfactants.
16. A solution according to claim 15 wherein the non-ionic
alkylated alkoxylate surfactants are polyoxyethylene
surfactants.
17. A solution according to claim 13 wherein the solution contains
at least one emulsifier, detergent and hydrotrope in a
concentration of from 0.04% w/w to 3% w/w.
18. A solution according to claim 13 wherein the corrosion
inhibitor is selected from the group consisting of benzotriazoles,
sodium nitrite, sodium molybdate, sodium gluconate, and sodium
benzoate.
Description
[0001] This application is a continuation of U.S. application Ser.
No. 13/426,191 filed Mar. 21, 2012, which is a continuation of U.S.
application Ser. No. 12/557,972 filed on Sep. 11, 2009 (now
abandoned), which is a divisional of U.S. application Ser. No.
11/518,188 filed on Sep. 11, 2006 (now U.S. Pat. No. 7,632,523),
which is a continuation of U.S. application Ser. No. 10/364,348
filed on Feb. 12, 2003 (now abandoned), which claims the benefit
under 35 U.S.C. section 119(e) of U.S. provisional application Ser.
No. 60/355,753 filed on Feb. 12, 2002 (now abandoned).
FIELD OF THE INVENTION
[0002] The present invention relates to disinfectants and, in
particular, it relates to hydrogen peroxide solutions with improved
disinfectant and antimicrobial properties.
BACKGROUND TO THE INVENTION
[0003] In the past few years, efforts have been concentrated on
developing chemicals that will be highly effective against
microorganisms when highly diluted, will be low in toxicity to
humans and other animals, and will not injure the environment. Of
the known disinfectants and antimicrobials, hydrogen peroxide
appears to have exceptional potential, especially in terms of
toxicity and injury to the environment, because the decomposition
products, water and oxygen, are benign. Also, it tends to have
broad spectrum antimicrobial activity. Broad spectrum activity is
important in situations where harmful organisms are present but
their identity is not known. Hydrogen peroxide based disinfectants
are useful in many different applications, including in hospitals,
clinics, laboratories, dental offices, home care and chronic care
facilities. They may also be used in food and beverage processing
and preparation, animal husbandry, the hospitality industry and for
general sanitation, e.g. janitorial services.
[0004] In order to provide fast, effective action, prior art
disinfectant solutions have had to employ relatively high
concentrations of hydrogen peroxide. At higher concentrations, the
solutions may not be practical or economically viable, may be
subject to hazardous goods regulations, and may require special
precautions for handling and use. For example, at concentrations of
above about 8% w/w aqueous solution, hydrogen peroxide is
considered corrosive, more so at higher concentrations, and is also
a strong oxidizing agent. Solutions containing less than about 8%
w/w hydrogen peroxide are preferred for their improved safety
profile. At concentrations of 1-3% w/w aqueous solution, hydrogen
peroxide is considered non-corrosive and non-irritating; at
concentrations of 3-7% w/w aqueous solution, hydrogen peroxide is
considered non-corrosive but an eye irritant.
[0005] Heretofore, one of the major drawbacks of hydrogen peroxide,
in very low concentrations, is that its antimicrobial action is too
slow. For example, prior art references indicate that a 0.1% w/w
aqueous solution of hydrogen peroxide requires 60 minutes to
disinfect surfaces contaminated with staphylococcus aureus, whereas
a 25.8% w/w aqueous solution of hydrogen peroxide requires only 20
seconds. The latter solution is clearly unacceptable from both
commercial and economic standpoints.
[0006] Attempts have been made to improve the efficacy of low
concentration hydrogen peroxide disinfecting solutions. For
example, Winterton et al. discloses, in U.S. Pat. No. 5,523,012, a
hydrogen peroxide disinfecting solution for contact lenses buffered
to a pH of about 6.9 and which has from about 0.1% w/w to about
1.0% w/w of an ocularly compatible surfactant. In one experiment,
the addition of about 0.4% anionic sulfosuccinate surfactant
improved the killing time for aspergillus fumigatus to 6.9 minutes,
compared to 12.3 minutes for a solution containing no added
surfactant. However, even 6.9 minutes is far too long for many
applications.
[0007] U.S. Pat. No. 5,264,229 to Mannig et al teaches a process of
extending the shelf life of commercially processed food products,
such as poultry, fowl and seafood products by contacting the food
products with a sufficient amount of food grade hydrogen peroxide
and food grade surface active agent selected from the group
consisting of alkyl aryl sulfonates, sulfates, sulfonates of fatty
acids, sulfates of alcohols and sulfosuccinates. The hydrogen
peroxide and surface active agent are present in chiller water in
which the food products are immersed and serve to remove and reduce
the number of bacteria on the surface of the food products. Up to 1
w/w hydrogen peroxide and from 5 to 100 ppm surface active agent
are used in the chiller water. The solutions of Mannig et al are
able to achieve only moderate levels of disinfectant activity using
a 45 minute contact time. While the Mannig solution may be
sufficient for preserving foods, it is inadequate for short contact
time disinfection.
[0008] Hydrogen peroxide is a compound which is highly susceptible
to decomposition by the presence of dissolved impurities, mostly
transition metal cations. Impurities causing hydrogen peroxide
decomposition are typically contained in either the water used in
preparation of a commercial disinfectant from an aqueous hydrogen
peroxide stock, or in the additional ingredients of the formulation
(i.e. surfactants, builders, etc.). The most effective method for
preventing decomposition of the hydrogen peroxide is by
sequestration or chelation of the dissolved catalytic metal
species, typically through the use of phosphate or phosphonate
compounds. The increased product shelf life gained by the use of
phosphorus stabilizers has allowed the commercial, albeit limited,
use of such compositions.
[0009] Most if not all peroxygen-based mixtures used for cleaning
and disinfection discussed in the prior art either suffer from
impracticably long contact times, unfeasibly high hydrogen peroxide
concentrations or contain at least one type of phosphorus compound
in non-trace quantities. Although the role of phosphorus in the
eutrophication of lakes and rivers due to artificial sources is
still a matter of debate, many regions in the world have imposed
severe restrictions on the amount of phosphorus that can be
discharged into storm and sanitary sewers.
[0010] In certain situations, it is therefore desirable to provide
a complex multicomponent hydrogen peroxide solution with the
capability of disinfection at short contact times, has low
non-hazardous concentrations of ingredients, and which contains no
phosphorus-based materials.
[0011] Though the prior art is replete with hydrogen peroxide
containing disinfectants, the present invention is intended to
provide an improved hydrogen peroxide disinfectant having enhanced
activity to permit rapid and effective disinfection of hard
surfaces and skin of humans and animals with a hydrogen peroxide
concentration as low as 0.5% w/w. Select embodiments of the present
invention do not contain any added phosphorus-based materials other
than those naturally present in commercial hydrogen peroxide stock
solutions, which are present in quantities permitted in
jurisdictions which impose restrictions on phosphorus discharge
into the environment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a graphical illustration of the cleaning
efficiency of Solution 2a, according to one embodiment of the
present invention, tested as described in Example 2 below against
commercial formulations;
[0013] FIG. 2 is a graphical illustration of the cleaning
efficiency of Solution 2b, according to another embodiment of the
present invention, tested as described in Example 2 below against
commercial formulations; and
[0014] FIG. 3 is a graphical illustration of the cleaning
efficiency of Solution 2c, according to yet another embodiment of
the present invention, tested as described in Example 2 below
against commercial formulations.
SUMMARY OF THE INVENTION
[0015] It has now been found that the addition of certain anionic
surfactants in certain concentrations greatly, and surprisingly,
enhances the bactericidal and/or virucidal activity of aqueous
acidic hydrogen peroxide solutions. Furthermore, by the careful
selection of the components in the mixture, solutions of
commercially acceptable stability and cleaning ability can be
achieved without the use of phosphorus containing stabilizers.
[0016] In accordance with a first aspect, the invention provides a
ready-to-use, aqueous disinfecting solution, having a pH of from
about 0.5 to about 6, and consisting essentially of: [0017] i)
hydrogen peroxide in a concentration of from about 0.05 to about 8%
w/w of the total solution; and [0018] ii) at least one anionic
surfactant chosen from C8 to C16 alkyl aryl sulfonic acids and
alkali metal, ammonium, ethanolamine, calcium and magnesium salts
thereof; sulfonated C12 to C22 carboxylic acids and alkali metal,
ammonium, calcium and magnesium salts thereof; C6 to C22 alkyl
diphenyl oxide sulfonic acids and alkali metal, ammonium, calcium
and magnesium salts thereof; naphthalene sulfonic acids and alkali
metal, ammonium, calcium and magnesium salts thereof; C8 to C22
alkyl sulfonic acids and alkali metal, ammonium, calcium and
magnesium salts thereof; alkali metal, ammonium, calcium and
magnesium C8 to C18 alkyl sulfates; alkyl or alkenyl esters or
diesters of sulfosuccinic acids in which the alkyl or alkenyl
groups independently contain from six to eighteen carbon atoms and
alkali metal, ammonium, calcium and magnesium salts thereof; and
mixtures thereof; in a concentration of from about 0.02 to about 8%
w/w of the total solution.
[0019] The concentration of the hydrogen peroxide may be from about
0.05, 0.1, 0.45, or 0.5% w/w of the total solution. Also, it may be
up to about 4, 2.5, 2, 1.2, or 1% w/w of the total solution.
Preferably, the concentration is from about 0.5 to 1.2% w/w.
[0020] The concentration of anionic surfactant may be from about
0.05 or 0.8 and up to about 6, 5, 4, 3.6, 2 or 1% w/w of the total
solution.
[0021] Furthermore, the pH of ready-to-use solutions may be from
about 0.7, 1.0, 1.5, 2, or 2.5 to about 4.5, 4.0, 3.5, 2.5, or 2%
w/w of the total solution, and preferably from about 1 to about 4.
In the case of hard surface disinfectants, the pH is more
preferably from about 1.5 to about 3.5, while in the case of
topical disinfectants, the pH is more preferably from about 2.5 to
about 4.5. Preferred concentrate versions of these solutions have
pH values ranging from about 0.7 to about 2. To achieve the
preferred pH values, buffering or other pH adjusting agents may be
added to the solution. These agents include organic and inorganic
acids or bases such as phosphoric acid, citric acid, sulfuric acid,
sodium hydroxide and potassium hydroxide, the latter being
otherwise known as caustic potash.
[0022] The anionic surfactant is preferably chosen from dodecyl
benzene sulfonic acid and alkali metal, ammonium, ethanolamine,
calcium and magnesium salts thereof; C6 to C22 alkyl diphenyl oxide
sulfonic acids and alkali metal, ammonium, calcium and magnesium
salts thereof; ethoxylated dodecyl sulfosuccinates, dioctyl
sulfosuccinates, ethoxylated dodecyl sulfosuccinates, and mixtures
thereof. More preferably, the anionic surfactant is chosen from
dodecyl benzene sulfonic acid and an alkali metal salt thereof, C6
alkylated sulfonated diphenyl oxide disodium salt, disodium dioctyl
sulfosuccinate, sodium lauryl sulfate, ammonium lauryl sulfate,
disodium lauryl ether sulfosuccinate ethoxylated to 3 moles of
ethylene oxide, and mixtures thereof.
[0023] Embodiments for use in topical applications (e.g.
formulations to be applied to the skin of humans or animals) should
contain those anionic surfactants which are mild to the skin,
including disodium dioctyl sulfosuccinate, sodium lauryl sulfate,
ammonium lauryl sulfate, disodium lauryl ether sulfosuccinate
ethoxylated to 3 moles of ethylene oxide, and mixtures thereof.
[0024] To further enhance the germicidal efficacy of the solution,
the solution may contain at least one additional ingredient chosen
from a monocarboxylic acid (e.g. acetic acid and glycolic acid), a
polycarboxylic acid (e.g. citric acid), benzyl alcohol, an alcohol
comprising one to eight carbon atoms (e.g. propylene glycol
n-propyl ether, ethylene glycol n-propyl ether, methanol, ethanol,
iso-propanol, n-butanol and n-pentanol), and mixtures thereof.
Preferred alcohols are the short chain (i.e. C1-C6) alcohols and
benzyl alcohol. The carboxylic acids have known pH buffering,
stabilizing and cleaning properties and are preferably present in a
total concentration of from about 0.1 to about 10% w/w, more
preferably from about 0.05 to about 4.0% w/w of the solution.
Preferred monocarboxylic acids are glycolic acid and acetic acid. A
preferred polycarboxylic acid is citric acid.
[0025] The alcohol is preferably present in a total concentration
of from about 0.1 to about 10% w/w of the total solution. In the
case of topical solutions, the alcohol is preferably present in a
concentration of from about 2 to about 5% w/w so that the solution
does not give rise to excessive drying and irritation. The recited
alcohols are believed to also provide additional cleaning
performance in respect of organic contaminants.
[0026] In accordance with a second aspect, the invention provides a
concentrated aqueous hydrogen peroxide solution which can be
diluted with water to produce a ready-to-use solution according to
the first aspect. Accordingly, the concentration of the ingredients
of the solution may be much higher than as stated above. For
example, the hydrogen peroxide concentration may be as high as 20%
w/w. Similarly, the anionic surfactant concentration may be as high
as 10% w/w. If the diluent is regular tap water which will likely
contain metal cations and other impurities serving to increase the
rate of hydrogen peroxide decomposition, hydrogen peroxide
stabilizers may be included in the solution. These will be
described further below.
[0027] The invention also provides, in accordance with a third
aspect, a solid disinfectant formulation which can be dissolved in
water to produce a ready-to-use solution according to the first
aspect. It will be clear to the person skilled in the art how to
manufacture such a solid formulation. In such embodiments, the
formulation comprises at least one hydrogen peroxide releasing
component, which may be chosen from sodium percarbonate, sodium
perborate monohydrate, and sodium perborate tetrahydrate.
Preferably, the component is sodium percarbonate or sodium
perborate. The anionic surfactants would be present either in salt
form or in acid form, as will be apparent to the person skilled in
the art.
[0028] Depending on the application, the present solution and solid
formulation may contain the following additional optional
ingredients which do not alter the basic and novel properties
thereof. The basic and novel properties are defined herein to mean
the bactericidal and/or virucidal activity of the solution and
solid formulation. The total amount of these optional ingredients
generally will not exceed 10% w/w of the final, total, ready-to-use
solution and often will not exceed about 7% w/w. In solid
embodiments of the invention, bulking agents may be included and,
in such case, the total amount of optional ingredients may exceed
10% w/w of the final, total, ready-to-use solution.
[0029] To improve stability of the solution, hydrogen peroxide
stabilizers may be added. In jurisdictions which do not impose
restrictions on phosphorus emissions, these stabilizers may be
based on phosphorus. These include:
1-hydroxyethylidene-1,1-diphosphonic acid, amino tri(methylene
phosphonic acid), 2-hydroxyethylimino tri(methylene phosphonic
acid), ethylene diamine tetra(methylene phosphonic acid),
phosphoric acid, and sodium tripolyphosphate. As well, foam
generating or stabilizing ingredients, emulsifiers, hydrotropes,
and detergents may be included. Emulsifiers and hydrotropes are
useful for maintaining phase stability, while detergents are useful
for cleaning soiled surfaces and to add foaming.
[0030] Preferred emulsifiers and detergents are non-ionic alkylated
alkoxylate surfactants, preferably polyoxyethylene surfactants.
Preferred polyoxyethylene surfactants are alkyl polyoxyethylene
surfactants and alkyl aryl polyoxyethylene surfactants. A preferred
alkyl polyoxyethylene surfactant which is a detergent is C6-C10
alkyl, 3.5 moles of ethylene oxide (EO) alcohol ethoxylate (AE)
sold in association with the trademark Alfonic L610-3.5. Also,
preferred alkyl aryl polyoxyethylene surfactants which are
emulsifiers are C8 to C16 alkylphenol alkoxylates. These include
octyl phenol ethoxylate which is sold in association with the
trademark Triton X-405.
[0031] The hydrotrope may be an anionic surfactant chosen from
alkylated sulfonated diphenyl oxides, alkylated sulfonated diphenyl
oxide salts, and mixtures thereof, and preferably is a C6 alkylated
sulfonated diphenyl oxide disodium salt.
[0032] Typically, the emulsifiers, detergents and hydrotropes are
present in a total concentration of about 10 to about 30 parts per
hundred parts of hydrogen peroxide or up to about 3% w/w of the
solution. Preferably, they are present in a concentration of from
about 0.04 to about 3% w/w, more preferably from about 0.04 to 2.0%
w/w, and even more preferably from about 0.1 to about 2.0% w/w of
the total solution.
[0033] To enhance the marketable qualities of the product, coloring
agents or dyes and scents or fragrances (e.g. oxycitrus fragrance)
may be added.
[0034] In topical solutions, thickening agents (e.g. acrylic and
biological polymers), moisturizing and other skin conditioning
agents may be added to improve the feel of the product and to
prevent drying of the skin.
[0035] Corrosion inhibitors may be added to embodiments of the
invention for use in cleaning non-ferrous metal substrates.
Examples include benzotriazoles (e.g. 1,2,3 benzotriazole,
hydrobenzotriazoles, carboxybenzotriazoles), sodium nitrite, sodium
molybdate, sodium gluconate, sodium benzoate, and combinations
thereof. Corrosion inhibitors may be present singularly or in
combination and will typically be present in a concentration of
from about 0.05 to about 10% w/w of the total solution, and
preferably from about 0.05 to about 1.5% w/w.
[0036] The present inventive solutions may be applied by spraying,
pouring or dipping, or through the use of dispensers, foaming
triggers or impregnated cloths.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0037] Unless the context dictates otherwise, all concentration
values are expressed based on the total solution or formulation of
the specified embodiment. The teen "consisting essentially of"
shall be construed to mean, including the listed ingredients and
such additional ingredients which do not materially affect the
basic and novel properties of the solution or solid formulation (as
applicable). The "basic and novel properties" are the bactericidal
or virucidal activity of the solution or solid formulation. Also,
when used herein, the term "about", when used in connection with a
specified value, means that value and such deviations therefrom
which do not materially affect the way the solution or solid
formulation works. Routine experiments may be performed to
determine whether there is a material effect or not. For the sake
of clarity, a material effect is an increase or decrease in
disinfecting performance of 0.03 log.sub.10.
[0038] In accordance with the first and second aspects of the
invention, the present inventive aqueous solution is made using
commercially available hydrogen peroxide solutions sold by Degussa
or FMC, for example. Such solutions are typically available as
aqueous solutions in a concentration of 35 or 50 w/w. As discussed
in, for example, Kirk-Othmer, "Encyclopedia of Chemical
Technology", vol. 13 M. Howe-Grant (ed.) (New York:
Wiley-Interscience, 1991) at page 965, these commercial solutions
always contain traces of catalytically acting impurities which
decompose the hydrogen peroxide, despite appropriate purification
measures. Thus, commercial solutions of hydrogen peroxide include
stabilizers in small amounts, i.e. measured in parts per million,
and have an excellent shelf life. These stabilizers work to
deactivate impurities, either by absorption or through the
formation of complexes. Known stabilizers for use in stabilizing
acidic hydrogen peroxide solutions include organic and inorganic
sequestering agents, i.e. stannates and phosphates, and
combinations of organic compounds and organometallic salts with or
without stannates and phosphates. An exemplary stannate is sodium
stannate trihydrate and an exemplary phosphate is sodium
pyrophosphate.
[0039] Solutions having from about 0.01 to about 1.0% w/w,
especially about 0.5% w/w hydrogen peroxide are suitable for use as
household and commercial disinfectants, bactericides and/or
virucides, sanitizers and cleaners. Solutions having about 3 to
about 4% w/w are suitable for use as multi-purpose cleaners and
bleach alternatives in healthcare facilities, households and
commercial facilities. Solutions having about 6 to about 8% w/w
hydrogen peroxide are suitable for use as sporicides, fungicides,
virucides and/or bactericides, broad spectrum sanitizers, general
purpose cleaners, and bleach alternatives, particularly in
institutional, healthcare and food applications, and are suited for
multiple level dilution according to the type of disinfection
task.
[0040] The anionic surfactant enhances the bactericidal and/or
virucidal activity of the solution. For bactericidal activity, the
C8 to C16 alkyl aryl sulfonic acids and their aforesaid salts are
preferred as they are widely available and relatively inexpensive.
They are also biodegradable. Preferred alkyl aryl sulfonic acids
and their salts are dodecyl benzene sulfonic acid, and tridecyl
benzene sulfonic acid and their salts, e.g. sodium, potassium,
ammonium salts. Especially preferred are dodecyl benzene sulfonic
acid and alkali metal or ammonium salts thereof.
[0041] The C6 to C22 alkyl diphenyl oxide sulfonic acids and alkali
metal, ammonium, calcium and magnesium salts thereof have been
found to impart virucidal activity to the solution. Preferred
members of this class include C6 and C10 alkylated sulfonated
diphenyl oxide disodium salts, and dodecyl diphenyl oxide
disulfonic acid and disodium 4-dodecylated diphenyloxide sulfonate.
The C6 alkylated sulfonated diphenyl oxide disodium salt is perhaps
the most preferred.
[0042] Of the sulfonated C12 to C22 carboxylic acids and their
aforesaid salts, sulfonated 9-octadecanoic acid, disodium 2-sulfo
C.sub.12-C.sub.18 fatty acid salts and sodium methyl 2-sulfo
C.sub.12-C.sub.16 esters are preferred.
[0043] A preferred salt of naphthalene sulfonic acid is sodium
alkyl naphthalene sulfonate.
[0044] Preferred salts of C8 to C22 alkyl sulfonic acids are sodium
octyl (C8) sulfonate, sodium C14-C17 sec-alkyl sulfonate, and the
sodium salts of 1-octane sulfonic acid, 1-decane sulfonic acid, and
tridecane sulfonic acid.
[0045] Of the aforesaid C8 to C18 alkyl sulfates, sodium lauryl
sulfate and sodium octyl sulfate are preferred. In topical
solutions, ammonium lauryl sulfate is also preferred. Of the alkyl
or alkenyl esters or diesters of sulfosuccinic acid in which the
alkyl or alkenyl groups independently contain from six to eighteen
carbon atoms and alkali metal, ammonium, calcium and magnesium
salts thereof, disodium lauryl sulfosuccinate and sodium dioctyl
sulfosuccinate are preferred in both hard surface and topical
solutions. Disodium lauryl ether sulfosuccinate ethoxylated to 3
moles of ethylene oxide is also preferred in topical solutions.
[0046] Complex mixtures based on hydrogen peroxide may be unstable,
with the hydrogen peroxide concentration diminishing greatly in
time due to catalytic decomposition. This may be acceptable in the
case of a dry powdered formulation which is used immediately after
dissolution in water. However, in the case of aqueous solutions
which are not used immediately modifications are required to
stabilize or mitigate the decomposition of the hydrogen peroxide. A
variety of factors influence the stability of hydrogen peroxide in
solutions, including the temperature, the concentration of hydrogen
peroxide, the pH value, and above all the presence of impurities
with a decomposing effect. We have found that, by the careful
selection of the adjuvant materials in the mixture, hydrogen
peroxide disinfectant solutions of commercial value can be prepared
without the addition of phosphorus-based stabilizers. This is of
advantage in jurisdictions which impose restrictions on phosphorus
emissions.
[0047] A first method of preparing an aqueous acidic solution
according to the first and second aspects of the present invention
comprises adding the anionic surfactant(s) and optional ingredients
such as emulsifiers, detergents, hydrotropes, alcohols, scents,
coloring agents, dyes, corrosion inhibitors, naturally occurring
carboxylic acids, etc., to distilled water or water purified by
other means. A commercially available hydrogen peroxide solution is
then added and, if necessary, buffering or other pH adjusting
agents are added to achieve the desired pH. A second method
involves preparing a powdered formulation by mixing together solid
forms of the ingredients of the present solution and then
dissolving the powdered formulation in water.
[0048] The invention may be better understood by reference to the
following examples. The following summary will assist in
determining the ingredients of the exemplary solutions.
Hydrogen Peroxide
[0049] The hydrogen peroxide used in all the examples, except for
example 10 and 14, is a 50% w/w technical grade commercial solution
manufactured by Degussa containing an effective amount of known
stabilizers, estimated at less than 50 ppm. In examples 10 and 14,
a 30% w/w hydrogen peroxide solution sold by Degussa was used.
Anionic Surfactants
[0049] [0050] Biosoft S-100.TM. (DDBSA)=dodecyl benzene sulfonic
acid; trademark of Stepan; commercially available as a 98% w/w
solution [0051] DOWFAX.TM. hydrotrope=C6 alkylated sulfonated
diphenyl oxide disodium salt; trademark of Dow Chemical (this
ingredient is also a hydrotrope); available commercially as a 45
w/w solution [0052] Dowfax C10L.TM.=C10 linear alkylated sulfonated
diphenyl oxide disodium salt; trademark of Dow Chemical; available
commercially as a 45% w/w solution [0053] Petro ULF.TM.
(ANS)=sodium alkyl naphthalene sulfonate; available commercially as
a 95 w/w solution [0054] Bioterge PAS-8.TM. (SOS)=sodium octyl
sulfonate; available commercially as a 38% w/w solution [0055]
Hostapur SAS-30.TM.=sodium C14-C17 sec-alkyl sulfonate; available
commercially as a 30% w/w solution [0056] Stepanol WAC.TM.
(SLS)=sodium lauryl sulfate; available commercially as a 29% w/w
solution [0057] Sipon LSB.TM.=sodium lauryl sulfate; manufactured
by Henkel; available commercially as a 30% w/w solution [0058]
Stepanol AM.TM.=ammonium lauryl sulfate; manufactured by Stepan;
available commercially as a 30% w/w solution [0059] Standapol
LF.TM. (SOS)=sodium octyl sulfate; available commercially as a 35%
w/w solution [0060] Stepan Mild SL3.TM. (DSLSS)=disodium lauryl
ether sulfosuccinate ethoxylated to 3 moles ethylene oxide (EO);
available commercially as a 32% w/w solution [0061] Alpha-Step
MC-48.TM. (SMSE/SFA)=solution containing SMSE and SFA (relative
ratio of components not given by manufacturer); available
commercially as a 37% w/w solution [0062] SMSE=sodium methyl
2-sulfo C.sub.12-C.sub.16 ester [0063] SFA=disodium 2-sulfo
C.sub.12-C.sub.18 fatty acid salt [0064] Aerosol OT-75.TM.=disodium
dioctyl sulfosuccinate; manufactured by CYTEC Inc.; available
commercially as a 75 w/w solution
Non-Ionic Surfactants
[0064] [0065] Surfonic L-610-3.TM.=C.sub.6-C.sub.10 alkyl, 3 mole
ethylene oxide alcohol ethoxylate; trademark of Huntington [0066]
Alfonic L610-3.5.TM.=C.sub.6-C.sub.10 alkyl, 3.5 moles of ethylene
oxide (EO) alcohol ethoxylate (AE); available commercially as a
100% w/w solution [0067] Triton X-405.TM. (OPE)=octyl phenol
ethoxylate; trademark of Union Carbide; available commercially as a
70% w/w solution [0068] Neodol 91-6.TM.=C.sub.9-C.sub.11, 6 moles
of ethylene oxide (50) alcohol ethoxylate (AE) (about 100% active
concentration) manufactured by Shell (for improving wetting and
feel) [0069] Ammonyx LO.TM.=lauramine oxide; manufactured by Stepan
(for flash foam stability)
Amphoteric Surfactants
[0069] [0070] Mirataine C-30.TM.=cocoamidopropyl betaine;
manufactured by Stepan (for flash foam stability); available
commercially as a 30% w/w solution
Hydrogen Peroxide Stabilizers
[0070] [0071] Briquest
ADPA-60AW.TM.=1-hydroxyethylidene-1,1,-diphosphonic acid; trademark
of Allbright & Wilson; is available commercially as a 60% w/w
solution
Moisturizing Agents
[0071] [0072] glycerin [0073] sorbitol [0074] Polyquaternium
11.TM.=polymeric quaternary ammonium polymer; manufactured by ISP;
available commercially as a 20% w/w solution
Thickening Agents
[0074] [0075] Keltrol RD.TM.=xantham gum; manufactured by Kelco
Biopolymers
Coloring Agents
[0075] [0076] FD&C Yellow No. 6
Buffering or pH Adjusting Agents
[0076] [0077] NaOH=sodium hydroxide
Example 1
[0078] Hard surface disinfectant solutions 1a and 1b were prepared
as shown in Table 1a below:
TABLE-US-00001 TABLE 1a Solution (% w/w) INGREDIENT 1a 1b Biosoft
S-100 0.15 0.15 BRIQUEST ADPA-60AW 0.47 0 H.sub.20.sub.2 0.60 0.60
deionized water balance to 100 balance to 100 pH 1.8 1.8
[0079] Solutions 1a and 1b were tested as specified in American
Society of Testing and Materials ("ASTM") standard quantitative
carrier test (ASTM Method E2111-00), described in the publication
entitled "Standard Quantitative Test Method to Evaluate the
Bactericidal, Fungicidal, Mycobactericidal and Sporicidal Potencies
of Liquid Chemical Germicides", American Society for Testing of
Materials, West Conshohocken, Pa.
[0080] The results are shown in Table 1b below:
TABLE-US-00002 TABLE 1b SAMPLE Control CFU Test CFU Log Reduction
Solution 1a 6.76 .times. 10.sup.6 0 6.76 Solution 1b 6.76 .times.
10.sup.6 0 6.76
[0081] The above results demonstrate that Solutions 1a and 1b are
effective in achieving a greater than 6 log reduction in bacterial
counts after a three minute contact time.
Example 2
[0082] Hard surface disinfectant solutions 2a, 2b and 2c were
prepared as shown in Table 2 below.
TABLE-US-00003 TABLE 2 Solution (% w/w) INGREDIENT 2a 2b 2c Citric
Acid 0.500 1.500 0.500 Acetic Acid 1.786 0.179 0.179 H.sub.2O.sub.2
1.000 1.000 1.000 Biosoft S-100 0.450 0.450 0.100 Dowfax Hydrotrope
0.300 0.300 0.300 Triton X-405 0.044 0.044 0.044 Surfonic L-610-3
0.150 0.150 0.150 pH 2.2 2.2 2.2
[0083] Solutions 2a, 2b, and 2c were tested using the Gardner scrub
test to determine the cleaning efficiency of such solutions as
compared to commercially available cleaners, namely Clorox Clean
Up.TM. and 409.TM.. The test procedure is described in the American
Society of Testing and Materials ("ASTM") D 4488-85 (Standard guide
for testing cleaning performance of products intended for use on
resilient flooring and washable walls) but using simulated test
soils better representing each application. Solution 2a was tested
on kitchen grease, Solution 2b was tested on bathroom soil, and
Solution 2c was tested on tea stains. Each of the specified soils
was applied to white vinyl tiles. Reflectance measurements were
recorded after each stroke of the Gardner scrubber and are plotted
in FIGS. 1 to 3.
[0084] FIG. 2 demonstrates that solution 2b is at least as
effective as the tested commercial solutions in cleaning bathroom
soil. FIG. 3 shows that solution 2c is as effective as 409 in
cleaning tea stains. FIG. 1 illustrates that while solution 2a is
not as effective as the tested commercial solutions in cleaning
kitchen grease, it is nonetheless somewhat effective.
Example 3
[0085] Hard surface disinfectant solutions 3a and 3b were prepared
as indicated in Table 3a below and tested in accordance with the
Official Methods of Analysis of the Association of Official
Analytical Chemists (A.O.A.C.) 16.sup.th Edition, 1995 Section
6.3.04, also referred to as the A.O.A.C. Official Method 961.02
titled "Germicidal Spray Products as Disinfectants", Final Action
1964. This method tests the effectiveness of sprays and pressurized
spray products as spot disinfectants for contaminated surfaces. The
tests used a contact time of 3 minutes against a 5% w/w soil load
of Staphylococcus aureus (ATCC No. 6538) and 60 slides. The results
are shown in Table 3b below. As shown, none of the 60 slides in
each experiment tested positive for the specified organism after
being exposed to the test solution.
TABLE-US-00004 TABLE 3a Solution (% w/w) INGREDIENT 3a 3b
H.sub.20.sub.2 0.5 1.5 Biosoft S-100 0.45 0.29 Acetic acid 0.3 1
Citric Acid 0.5 0.5 Dowfax hydrotrope 0.135 0.135 Triton X-405
0.0443 0.0443 Surfonic L610-3 0.15 0.15 deionized water 97.92 96.4
pH 2.2 2.2
TABLE-US-00005 TABLE 3b Germicidal Test Results Test Organism
Solution 3a Solution 3b Staphylococcus aureus (ATCC No. 6538) test
not 0/60 performed Salmonella choleresuis (ATCC No. 10708) 0/60
0/60
[0086] Solutions 3a and 3b were also tested for stability using a
hot stability test such as that described in U.S. Pat. No.
5,736,497 to Steiner. The results are summarized in Table 3c
below.
TABLE-US-00006 TABLE 3c Stability Test Solution 3a Solution 3b
Stability (20 hours @ 97.degree. C.) 96.4 .+-. 0.5% 95.9 .+-.
0.5%
[0087] The results indicate that upon storage of the solutions at
room temperature, more than 95% of the hydrogen peroxide is
expected to remain in solution for a period of at least one
year.
Examples 4 to 8
[0088] Additional exemplary embodiments of the present inventive
solution useful as hard surface disinfectants are summarized in
Tables 4 to 8 below.
TABLE-US-00007 TABLE 4 Solution (% w/w) INGREDIENT 4a 4b 4c Dowfax
Hydrotrope 0.08 -- 0.08 Biosoft S-100 0.18 0.18 0.18 Triton X-405
0.06 -- 0.04 H.sub.2O.sub.2 1 1 0.55 pH 1.91 1.97 1.91 deionized
water to 100 to 100 to 100
TABLE-US-00008 TABLE 5 Solution (% w/w) INGREDIENT 5 Dowfax
Hydrotrope 0.08 Alfonic L610-3.5 0.05 Hydrogen Peroxide 0.55
Biosoft S-100 0.18 pH about 2 deionized water to 100
TABLE-US-00009 TABLE 6 Solution (% w/w) INGREDIENT 6a 6b 6c d 6e
Dowfax Hydrotrope 0.08 0.08 0.08 0.08 0.08 Alfonic L610-3.5 0.05
0.05 0.05 0.05 0.05 Hydrogen Peroxide 0.55 0.55 0.55 0.55 0.55
Dowfax C10L -- 0.18 -- -- -- Stepan Mild SL3 (SLSS) -- -- 0.17 --
-- Petro ULF (ANS) -- -- -- 0.17 -- Stepanol WAC (SLS) -- -- -- --
0.16 Biosoft S-100 0.18 -- -- -- -- pH about 2 about 2 about 2
about 2 about 2 deionized water to 100 to 100 to 100 to 100 to 100
Solution (% w/w) INGREDIENT 6f 6g 6h 6i 6j Dowfax Hydrotrope 0.08
0.08 0.08 0.08 0.08 Alfonic L610-3.5 0.05 0.05 0.05 0.05 0.05
Hydrogen Peroxide 0.55 0.55 0.55 0.55 0.55 Hostapur SAS-30 -- --
0.18 -- -- Standapol LF -- -- -- 0.18 -- Alpha-Step MC-48 -- 0.16
-- -- -- Bioterge PAS 8 0.17 -- -- -- -- pH about 2 about 2 about 2
about 2 about 2 deionized water to 100 to 100 to 100 to 100 to
100
TABLE-US-00010 TABLE 7 Solution (% w/w) INGREDIENT 7a 7b 7c Dowfax
Hydrotrope 0.08 0.08 0.08 Alfonic L610-3.5 0.05 0.05 0.05 Hydrogen
Peroxide 0.55 0.55 0.55 Biosoft S-100 0.18 0.18 0.18 NaOH (50%) to
pH shown pH 3.8 pH 5.0 pH 6.0 deionized water to 100 to 100 to
100
TABLE-US-00011 TABLE 8 Solution (% w/w) INGREDIENT 8a 8b 8c 8d 8e
Dowfax Hydrotrope 0.08 -- 0.08 0.08 0.08 Alfonic L610-3.5 0.05 0.05
-- 0.05 0.05 Hydrogen Peroxide 0.55 0.55 0.55 0.55 0.55 Biosoft
S-100 0.18 0.18 0.18 -- 0.18 Phosphoric acid (75%) 0.06 -- -- 0.11
-- (for adjusting pH to about 1.8) pH about about about about about
1.8 1.8 1.8 1.8 1.8 deionized water to 100 to 100 to 100 to 100 to
100
Example 9
[0089] Hard surface disinfectant solution 9 was prepared as shown
in Table 9a below and tested in accordance with ASTM Method
E2111-00 (described above) against the polio virus, and in
accordance with the A.O.A.C. 960.09 method, titled "Germicidal and
Detergent Sanitizing Action of Disinfectants." Final Action
A.O.A.C. XV, 1995, Part 6.3.03 (hereinafter referred to as the
"A.O.A.C. 960.09 method"), against Staphylcoccus aureus. The
A.O.A.C. method is a suspension test standardized b the A.O.A.C.,
Association of Official Analytical Chemists, which uses a contact
time of 30 seconds. The results are shown in Table 9b below.
TABLE-US-00012 TABLE 9a Solution (% w/w) INGREDIENT 9 Biosoft S-100
(98% DDBSA) 2.5 Dowfax C10L (C10 Linear Diphenyl Disulphonate 1.0
(39%) Alfonic 610-3.5 (Linear Alcohol Ethoxylate (100%) 0.7
Hydrogen Peroxide (30%) 3.7 Briquest ADPA-60AW 0.0 deionized water
86.8 sulfuric acid to adjust pH to 0.9 pH 0.9 Total 100.0
TABLE-US-00013 TABLE 9b Test Organism (test # of Contact Contact
CFU/control CFU/test Log.sub.10 method) Carriers Dilution Temp Time
Carrier Carrier Red'n Polio 6 1:16 room 5 min 8.9 .times. 10.sup.3
0 3.95 Virus temp. (ASTM Method E2111-00) S. aureus 6 1:64 room 30
sec. 9.4 .times. 10.sup.6 12 5.88 (A.O.A.C. temp. 960.09
method)
[0090] The results indicate that Solution 9 is an effective
virucide and bactericide.
Solutions for Topical Application
[0091] The hands carry a variety of microorganisms which can be
classified as transient or resident. Transient organisms do not
grow naturally on the hands, while resident organisms grow
naturally on the skin and are harder to remove. The most important
transient species are gram negative bacilli such as Salmonella
spp., Escherichia coli, Pseudomonas aeruginosa, Klebsiella spp.,
and Staphylococcus aureus. Resident organisms consist mainly of
Staphylococcus epidermidis and other coagulase-negative
staphylococci, micrococci, and cornynebacteria (Ayliffe G. A. J.,
Babb, J. R. and H. A. Lilly, "Tests for Hand Disinfection",
Disinfectants: Their use and evaluation of effectiveness, Collins
C. H., M. C. Allwood, S. F. Bloomfield and A. Fox (eds), Academic
Press, London, UK, 1981). As a consequence, hand washing and
disinfection play an important role in biosafety control in the
health and dental care, veterinary care, and food handling and
processing industries.
[0092] In large scale farming operations, animals are typically in
close contact with each other and/or with pieces of equipment.
Disease-causing organisms are easily transmitted from one animal to
another and from equipment to animals. An example of a disease of
economic importance is mastitis, which is an inflammation of the
mammary glands of bovine species, caused by the presence of
bacteria, the most common of which are Staphylococcus aureus,
Streptococcus agalactiae, Streptococcus dysagalactiae and
Streptococcus uberis. Mastitis results in lower milk yields and
lower mild quality. Thus, its prevention through the combination of
therapy and hygiene techniques is of paramount importance. Current
prevention techniques consist of spraying, dipping or massaging the
udder with a disinfectant liquid in order to maintain the bacterial
population numbers under control.
[0093] In the control of mastitis, organisms need to be destroyed
in very short periods of time, typically no longer than 1 minute,
as the disinfectant solution is most easily applied to each animal
after it is milked. The disinfecting solution must also be
effective against a wide range of gram positive and gram negative
organisms, and its activity should not be neutralized by the
presence of an organic load. The antimicrobial active should be
non-toxic to both the animal and the user, and should not
contaminate the milk. Also, the mastitis-prevention composition
should not irritate or cause the teat to peel, which will result in
udder pain and ultimately affect the milk yield.
[0094] The invention provides embodiments which are useful in
disinfecting the skin of humans and animals in contact times of
less than 1 minute. These embodiments are designed to not only
mitigate bacteria, but also to clean the skin without producing
adverse effects with frequent use. They are designed to be used as
an antimicrobial hand wash for health workers, a surgical scrub
solution, a preoperative skin decontamination solution, or a wound
cleanser and disinfectant. They may also be used for the periodic
treatment of bovine teats for the prevention of mastitis.
[0095] In these embodiments, hydrogen peroxide is present in a
concentration of between about 0.1 and about 2.5% w/w, with the
preferred range being from about 0.45 to about 1.20% w/w. Higher
concentrations of hydrogen peroxide may result in excessive skin
irritation and in some cases temporary whitening of the skin Lower
concentrations of hydrogen peroxide may result in excessively weak
biocidal activity, rendering the solution practically
ineffective.
[0096] The anionic surfactants are preferably chosen from alkali
metal, ammonium and ethanolamine salts of dodecyl benzene sulfonic
acid, dodecyl sulfate, ethoxylated dodecyl sulfates, dioctyl
sulfosuccinates and ethoxylated dodecyl sulfosuccinates. The
preferred components are ammonium lauryl sulfate, disodium dioctyl
sulfoccinate and disodium lauryl ether sulfosuccinate with 3 moles
EO of ethoxylation. These ingredients are present in a total
concentration of 0.5 to 8.0% w/w of the total solution, with the
preferred range being between 0.9 to 2.0% w/w. These selected
surfactants do not generally result in excessive drying of the skin
or irritation and are preferably used in combination rather than
singularly, as this is believed to result in less skin
irritation.
[0097] The solution may contain a sufficient amount of buffers or
other pH adjusting agents to adjust the pH to--and maintain the pH
during storage in--the desired range, which is between about 1 and
about 4.5, and preferably between about 2.5 and about 4.5. Examples
of suitable buffers or other pH adjusting agents include weak
organic or inorganic acids, such as citric or phosphoric acids.
Alternatively, traditional strong basic pH adjusting agents (e.g.
sodium or potassium hydroxide) can also be utilized in order to
raise the pH of the mixture to the desired range.
[0098] To further enhance the biocidal activity of the solution,
benzyl alcohol and/or a short chain C.sub.2-C.sub.6 alcohol may be
utilized in a low enough concentration so as to not render the
solution flammable, and to not give rise to a strong alcoholic
odor. Particularly preferred short chain alcohols are
C.sub.3-C.sub.5 aliphatic alcohols, and more particularly preferred
are n-butanol and n-pentanol in concentrations of between about 2
and about 5 w/w.
[0099] Additional optional ingredients include organic
phosphorus-based hydrogen peroxide stabilizers (e.g. solutions sold
by Solutia in association with the trade name Dequest.TM., or by
Allbright and Wilson in association with the trade name
Briquest.TM.. A particularly preferred example is
1-hydroxyethylidene-1,1-diphosphonic acid available commercially as
Briquest ADPA-60AW.TM. from Allbright and Wilson, or as Bequest
2010.TM. from Solutia. Of course, if the solution is to be used in
jurisdictions which impose restrictions on phosphorus emissions,
these ingredients may be replaced with phosphorous free stabilizers
such as 8-hydroxyquinoline, stannates, citric acid,
nitrilotriacetic acid, and ethylenediamine tetraacetic acid.
[0100] The solution may contain skin conditioning and moisturizing
agents such as those hydrophobic materials widely known in the art
(e.g. glycerin, glycerol, polyquaternium compounds, guar gums, and
low hydrophile liyophile balance non-ionic surfactants). Gelling
and other viscosity modifying agents can be employed, including
cellulosic esters and ethers, acrylic polymers, biological
polymers, and sodium chloride in combination with viscosity
modifying surfactants. Finally, dyes and fragrances can be utilized
to impart color or specific aromas.
[0101] The following are examples of embodiments for use in topical
applications.
Example 10
[0102] Four antimicrobial solutions (Solutions 10a, 10b, 11a, and
11b) were prepared and evaluated for use in the control of
mastitis. The solutions are summarized in Tables 10a and 11a below.
The anionic surfactant Aerosol OT-25 is a disodium dioctyl
sulfosuccinate manufactured by CYTEC Inc., while the Sipon LSB is a
sodium lauryl sulfate manufactured by Henkel. The nonionic
surfactant Neodol 91-6 manufactured by Shell is included for
improving wetting and feel. Moisturizing is imparted by glycerin,
sorbitol, while the viscosity was raised by using xantham gum
(Keltrod RD manufactured by Kelco Biopolymers).
TABLE-US-00014 TABLE 10a Comparative examples of solution for use
in the control of mastitis Solution (% w/w) INGREDIENT 10a 10b
Citric Acid (99%) 0.05 0.05 Briquest ADPA-60AW 0.05 0.05 Aerosol
OT-75 -- 1.00 Sipon LSB -- 1.00 Neodol 91-6 -- 0.40 Hydrogen
Peroxide (30%) 1.67 1.67 Keltrol RD (xantham gum) 0.10 0.10
Glycerin (99%) 3 3 sorbitol (99%) 3 3 FD&C Yellow No. 6 0.05
0.05 NaOH (50%) qs to pH 4.5 qs to pH 4.5 deionized water 86.63
84.23
TABLE-US-00015 TABLE 10b Efficacy Data Solution 10a Solution 10b
Log.sub.10 reduction in the presence of 10% milk; <3.37 <5.37
Staphylococcus aureus at 30 sec contact time
[0103] Solutions 10a and 10b were evaluated according to a
suspension test similar to that described in the A.O.A.C. Method
960.09 (cited more completely above), except that the germicide
solution was replaced with a mixture of the geiuiicide solution and
milk, at a milk concentration of 10% w/w. The results are shown in
Table 10b above. The pass criteria is a Log.sub.10 reduction of
greater than 5.0. Solution 10b is in accordance with the present
invention. Solution 10a differs from Solution 10b in that the
anionic surfactants were excluded. This experiment demonstrates
that the absence of the anionic surfactants (in this case, sodium
lauryl sulfate and dioctyl sulfosuccinate) results in a decrease in
activity, even in the presence of close to a 2% active
concentration of hydrogen peroxide, and an acid pH.
Example 11
[0104] Solutions 11a and 11b were prepared in accordance to the
present invention and summarized in Table 11a below. These
solutions contain additional surfactants for improved flash foam
for dispensing as a wet foam. In this case, the solutions contain
the anionic surfactants ammonium lauryl sulfate (Stepanol AM
manufactured by Stepan) and disodium lauryl sulfosuccinate
ethoxylated to 3 moles ethylene oxide (BO) (Stepan Mild SL3,
manufactured by Stepan). Flash foam stability is provided by the
amphoterics, cocoamidopropyl betaine (Mirataine C-30, manufactured
by Stepan), and a non-ionic surfactant, lauramine oxide (Ammonyx
LO, manufactured by Stepan). Skin emollients are also included,
namely glycerin and the polymeric quaternary ammonium polymer,
Polyquaternium 11 (manufactured by ISP). The solutions at 55%
strength were tested in accordance with the A.O.A.C. 960.09 method
and the results are shown in Table 11b below.
TABLE-US-00016 TABLE 11a Efficacy of antimicrobial hand wash
solutions Solution (% w/w) INGREDIENT 11a 11b Citric Acid (99%)
0.05 0.05 Brisquest ADPA-60AW 0.05 0.75 H.sub.2O.sub.2 (50%) 2.0
2.0 Glycerin 3.0 3.0 Mirataine C-30 (30% betaine) 0.6 0.6 n-butanol
4.0 -- Stepanol AM (30% Ammonium LS) 5.0 5.0 Stepan Mild SL3 (32%
DSLSS) 4.0 4.0 Ammonyx LO (30% Lauramide oxide) 0.69 0.69
Polyquaternium 11 (20%) 2.0 2.0 pH 3.0 2.5 deionized water q.s. to
100%
TABLE-US-00017 TABLE 11b Log Reduction Solution 11a 11b Efficacy at
a contact time of 30 secs at 55% strength Staph. Aureus >6.00
>6.00 Escherichia coli >6.00 >6.00
[0105] Solutions 11a and 11b far surpass the requirements of
greater than 3-log reduction in the viable numbers of the test
organisms at a dilution of 55% and a contact time of 30
seconds.
Example 12
[0106] Solution 11b was tested further against other organisms
cited in the European standard for hand wash disinfection. The
method used was the A.O.A.C. 960.09 method modified by replacing
the germicide solution with a mixture of the germicide solution and
milk, wherein the milk concentration was 10% w/w. The results shown
in Table 12 below demonstrate that this solution conforms to the
minimal standards required for antimicrobial hand washes by the
European community
TABLE-US-00018 TABLE 12 Efficacy of antimicrobial hand wash per
European standard EN 12054 Log.sub.10 reduction reduction in the
presence of 10% milk; Staphylococcus aureus at 30 sec Test Organism
contact time Pseudomonas aeruginosa 8.13 Staphylococcus aureus 7.70
Escherichia coli 7.64 Enterococcus. hirae 7.93
Example 13
[0107] Solutions 11a and 11b were evaluated for their irritation to
skin according to the OECD standard 404 for measuring skin
irritancy of chemicals. The results, and the interpretation of the
irritation scores per OECD 404, are included in Table 13 below.
TABLE-US-00019 TABLE 13 Irritation indexes compared to commercial
antimicrobial hand washes Response Primary Category per Sample
Irritation Index OECD 404 Commercial Triclosan-based hand 3.00
Moderate irritant wash Solution 11b 0.58 Slight irritant Commercial
PCMX-based hand wash 2.25 Moderate irritant Solution 11a 0.92
Slight irritant
[0108] The results show that solutions 11a and 11b, in spite of
their strong antimicrobial activity, exhibit milder irritation
profiles than currently commercially available products which are
based on more traditional antimicrobial agents.
Example 14
[0109] Solutions 14a, 14b, 14c were prepared in accordance with
Table 14a below. These solutions are suitable for cleaning teats of
bovine animals and were tested in accordance with the A.O.A.C.
960.09 suspension test method, modified by replacing the germicide
solution with a germicide and milk solution, wherein the milk
concentration was 10% w/w. The results, summarized in Tables 14b
and 14c below, indicate that the solutions passed this test, as a
greater than 5 log reduction in a 30 second contact time was
achieved.
TABLE-US-00020 TABLE 14a Solution (% w/w) INGREDIENTS 14a 14b 14c
deionized water 83.00 (qs to 100) Keltrol RD 0.10 Briquest ADPA-60
AW 0.05 Stepanol AM 0.33 Hydrogen Peroxide (30%) 1.00 Glycerol 3.00
Sorbitol 3.00 NaOH Up to pH = 4.5 citric acid 1.00 1-butanol 4.00
0.00 0.00 benzyl alcohol 0.00 3.50 2.5 Aerosol OT-75 0.00 0.5 0.5
pH 4.50 4.50 4.50 Total 100.00 100.00 100.00
TABLE-US-00021 TABLE 14b The activity against E. coli (suspension
test method) Average # of Contact CFU/ml CFU/ml Average Solution
Dilution Repeats Time control test Log.sub.10 Red'n 14a Full 4 30
sec 0.97 .times. 10.sup.6 0 5.99 Strength 14b Full 4 30 sec 0.97
.times. 10.sup.6 0 5.99 Strength 14c Full 4 30 sec 0.97 .times.
10.sup.6 0 5.99 Strength
TABLE-US-00022 TABLE 14c The activity against S. aureus (suspension
test method) Average # of Contact CFU/ml CFU/ml Average Solution
Dilution Repeats Time control test Log.sub.10 Red'n 14a Full 4 30
sec 1.24 .times. 10.sup.6 0 6.09 Strength 14b Full 4 30 sec 1.24
.times. 10.sup.6 0 6.09 Strength 14c Full 4 30 sec 1.24 .times.
10.sup.6 0 6.09 Strength
[0110] The person skilled in the art will appreciate that many
obvious modifications to the above examples may be made without
changing the essence thereof. The foregoing description is by way
of example only and shall not be construed so as to limit the scope
of the invention which is defined by the following claims.
* * * * *