MX2008000610A - Enhanced tuburculocidal activity and decreased fumes from glutaraldehyde disinfectant using acetate salts and alcohol - Google Patents

Abstract

The addition of alcohol plus acetate salts unexpectedly enhanced the tuberculocidal activity of glutaraldehyde, and decreased the fumes of glutaraldehyde from the formula of a high-level disinfectant.

Description

DISINFECTANT OF GLUTARALDEHYID WITH GREATER ACTIVITY TUBERCULOCIDA AND LESS TRAINING OF VAPORS THAT USA ACETATE AND ALCOHOL SALTS Field of the Invention This invention is an improvement to my North American patent no. 5,863,547 dated January 26, 1999. Recently discovering that the addition of alcohol and acetate salts are necessary for a disinfectant with a high level of glutaraldehyde to kill mycobacteria (TB), vegetative Gram-positive and Gram-negative bacteria, fungi and virus in the course of 10 minutes at 20 ° C. In addition, the vapors of glutaraldehyde are significantly summarized by the combination of alcohol and acetate salts. As a result, faster elimination and fewer vapors are obtained for an improved formulation based on glutaraldehyde for high-level disinfection and / or sterilization of reusable heat-sensitive medical, dental and veterinary devices. The description of my prior North American patent 5,863,547 of January 26, 1999 is incorporated by reference. BACKGROUND OF THE INVENTION Many medical devices are constructed of heat-sensitive polymeric materials, glues, glass lenses, and electronic components. Examples of these devices are gastroscopes, colonoscopes, cystoscopes, arthroscopes, transesophagal and vaginal areas, and equipment for anesthesia and respiratory therapy. These heat sensitive devices are very expensive, and therefore are typically used in many patients and can not be sterilized by steam or dry heat. These heat sensitive devices are therefore disinfected with the highest levels of liquid chemical disinfectants. High-level disinfectants are capable of killing Gram-positive and Gram-negative vegetative bacteria, mycobacteria such as Mycobacterium tuberculosis, fungi and all types of viruses, with relatively short exposure, and can also kill a large number of bacterial spores that are They have dried on the surface with a much longer exposure time. The chemistries of the high-level disinfectants that are available to disinfect medical devices are glutaraldehydes, other aldehydes such as ortho-phthalaldehydes and formaldehyde, paracetic acid, hypochlorous acid and chlorine dioxide. These chemicals have serious limitations as high-level disinfectants. Glutaraldehyde requires approximately 45 minutes at 25 ° C to kill 6 log 10 of mycobacteria and approximately 10.0 hours at 25 ° C to kill bacterial spores as measured by the sporicidal test of the Official Analytical Chemists (AOAC) 966.04. These are impractical exposure times and temperatures that are often arbitrarily reduced in practice. Glutaraldehyde has a serious problem of odor and sensitization that requires special equipment to house and expel the vapors. Formaldehyde is a known carcinogen with a noxious odor. Ortho-phthalaldehyde has vapors that are relatively odorless, but vapors can sensitize patients and staff. Some patients and workers have been sensitized to ortho-phthalaldehyde, and have reacted with anaphylactic shock from repeated exposure to vapors that they can not smell. The ortho-phthalaldehyde requires approximately 32 hours to kill the bacterial spores in the sporicidal test (AOAC) 966.04. The ortho-phthalaldehyde is relatively insoluble and thus difficult to remove from surfaces. The aldehydes can be used and re-used for typically 14 to 30 days. Paracetic acid has a pungent odor that must be contained within a machine, and the product is used at a temperature of 50 ° C to 56 ° C. The combination of the oxidizing para-acetic acid used at relatively high temperatures of 50 ° C to 56 ° C can be harmful to some glues and polymeric materials. All oxidizing chemicals such as paracetic acid, hypochlorous acid and chlorine dioxide are unstable and thus are single or daily use products. Therefore, there is a need for a high-level disinfectant that can be disinfected with a practical exposure time and ambient temperature, with a safe and detectable odor, and with a suitable period of use to use and reuse for many years. days. Towards the end of my previous American patent was a first-stage improvement.

We previously discovered that relatively low concentrations of alcohol improves the mycobactericidal activity of glutaraldehyde (U.S. Patent No. 5,863,547). This patent, however, specifically teaches avoiding the addition of acetate salt (column 2, lines 28-30). Furthermore, studies have now discovered that acetate salts in combination with alcohol are necessary to optimize the mycobactericidal activity of glutaraldehyde for a very fast and practical exposure time and temperature such as 10.0 min at 20 ° C. Another surprising discovery was that the glutaraldehyde vapors were greatly reduced by the presence of alcohol and acetate salts at appropriate levels. With the addition of acetate salts, the pH value of a non-activated glutaraldehyde solution increased to approximately 6.5. The stable pH value for glutaraldehyde is about 3.5 to 4.5. Due to the pH value of 6.5, the concentration of glutaraldehyde in the non-activated formulation was slowly reduced during a period of approximately 9 to 12 months of storage in a cellar. For example, it was necessary to start with a glutaraldehyde concentration of approximately 3.5% in order to have a glutaraldehyde concentration of at least 2.0% after 12 months of storage, followed by 14 days of use and re-use. The repeated use of the disinfectant inadvertently dilutes the concentration of glutaraldehyde since the freshly cleaned wet devices carry some water in the disinfectant, and the newly disinfected devices carry some glutaraldehyde that is rinsed. Also because of the inadvertent dilution that occurs during the 14 days of use and re-use, it is necessary to start with a somewhat higher amount of alcohol, this is up to approximately 26% alcohol in order to have approximately 1 5% of alcohol after inadvertent dilution caused by the use and re-use. Acetate salts should also start at a concentration greater than about 8% in order to maintain a minimum effective concentration of about 5% after use and reuse for 1 4 days. The effective concentration as the term aq u is used means the concentration after approximately 14 days of use and reuse. It is a primary objective of the present invention to improve the formulation of my prior US patent no. 5,863,547 in several important ways. First, increase the rate of anti-microbial annihilation; second, modify the formulation in such a way as to maintain a minimum effective concentration even after use and re-use, for example for 14 days; third, to improve the mortality rate and the effectiveness of the disinfectant by adding acetate salts at levels of 3 to 8%; and fourth, by surprisingly reducing the acid odor of glutaraldehyde vapors by means of the combination of the acetate salts present and the alcohol that is present. The method and manner of achieving this primary objective as well as others will be apparent from the following description of the invention. Brief Description of the Invention This invention discloses a high level disinfectant formulation which can rapidly disinfect medical heat sensitive devices, for example within 10.0 minutes at room temperature, and which also has detectable but relatively low glutaraldehyde vapors. The formula contains glutaraldehyde (2.0% to 5.0%) plus alcohol (5% to 26%), plus acetate salts (3% by weight to 8% by weight), all buffered at the time of use with an alkaline buffer system at a pH value of 7.3 to 7.9. This stabilizes the glutaraldehyde during a period of 14 days of use and re-use. The worst-case concentrations of this formula can kill bacterial spores as measured by the sporicidal test (AOAC) 966.04 for 6.0 hours at 20 ° C. Glutaraldehyde vapors are reduced by up to 75%, not due to the reduction of glutaraldehyde concentration, but rather due to the presence of alcohol and acetates salts. These discoveries will provide a better high-level disinfectant formulation with practical exposure times and temperatures. Detailed Description of the Invention Glutaraldehyde is the first ingredient of the composition and may be present in the initial amount between about 2.0% and 5.0% by volume. Unless otherwise specified, the percentage ranges expressed here are in volume. Preferably the initial concentration of glutaraldehyde is 3.5% by volume such that the concentration of glutaraldehyde can remain at or above 2.0% during storage and use and reuse for 14 days. The acetate salts will increase the pH value during storage and use and re-use for 14 days. The acetate salts will increase the pH value during storage of the formulation to about 6.5. Glutaraldehyde is most stable at a pH value of about 3.5 to 4.5. During storage in warehouses for a period of approximately 12 months at a pH of 6.5, the concentration of glutaraldehyde will gradually decrease. So it is necessary to start with the highest concentration of glutaraldehyde to maintain the minimum concentrations after storage in the cellar and 14 days of use and re-use. Glutaraldehyde provides the primary antimicrobial activity of the composition. Alcohol is the second ingredient of the composition. Alcohols suitable for use in the present invention are alcohols miscible with straight or branched chain water, including methanol, ethanol and isopropanol as well as others. Isopropanol and ethanol are preferred. The alcohol is present in a concentration of about 5% to about 26% by volume. The preferred concentration of alcohol is 24-26% by volume. This concentration of alcohol gradually improves the tuberculocidal activity of, for example, up to 2.0% glutaraldehyde. Alcohol alone is not tuberculocidal at 5 to 20% by volume, nor is 2.0% glutaraldehyde tuberculocidal at 20 ° C within a practical exposure time of 10 minutes. However 5.0% to 26% by volume of alcohol in combination with for example 2.0% glutaraldehyde is rapidly tubercolocid in the course of 10 minutes at 20 ° C. A further improvement to the tuberculocidal activity of glutaraldehyde with acetate allows the concentration of glutaraldehyde in the formula to be reduced. Isopropyl alcohol is the second preferred ingredient of the composition and may be present in a preferred starting amount of between 24% and 26% by volume. Isopropyl alcohol will remain stable during storage in a warehouse. When the disinfectant is used and re-used for 14 days some of the alcohol will evaporate and some of the alcohol will inadvertently be diluted as the equipment carries water to the disinfectant, and the newly disinfected equipment will carry alcohol that will be rinsed. Therefore it is necessary to start with for example about 26% of the initial volume of alcohol in order to have at least 15% alcohol after 14 days of using and reusing the disinfectant. The preferred isopropyl alcohol in combination with the acetate salts greatly improves the tuberculocyte activity of glutaraldehyde and the alcohol also suppresses the foaming of the composition as would otherwise occur when the surfactant is added. The acetate salts preferably the potassium or sodium acetate salts are the third ingredient of the composition and may be initially present at about 3 wt% to 8 wt%. Acetate salts are stable during storage in the cellar. It is necessary to start with approximately 8% acetate salts by weight in order to have at least 5%, the minimum effective level preferred after using and reusing the disinfectant for 14 days. Acetate salts in combination with alcohol greatly improve the tuberculocidal activity of glutaldehyde. The acetate salts also improve the sporozoid activity of the composition. The acetate salts in addition to the alcohol surprisingly also suppress the glutaraldehyde vapors which is obviously desirable. A buffer, preferably a phosphate buffer, is the fourth ingredient of this disinfectant formulation. Glutaraldehyde is stable in this composition stored at about pH 7.3 to 7.9 for 14 days during use and reuse. Shock absorbers other than phosphate salts cause a 40% reduction in the glutaraldehyde concentration of activated disinfectants with for example, bicarbonate buffers. As a result, phosphate is preferred. It is important that the composition has a concentration of glutaraldehyde that remains stable for 14 days of use and re-use. This chemical stability during the 14 days of use and re-use provides more glutaraldehyde for antimicrobial activity at any given time than if the composition had been buffered with another buffer. The amount of shock absorber is 4 g / liter. In the preferred composition as in the composition of my previous patent, there is a surfactant. Preferred levels of surfactant are 0.0025% by weight to 0.01% by weight. The suitable surfactant is not critical and basically the same surfactants that are used in the list may be used in my previous patent which is incorporated herein by reference. Together this combination of glutaraldehyde in 2% to 5%, alcohol to 5% to 26%, salts of acetate at 3% by weight to 8% by weight, a non-ionic surfactant with low foaming, at 0.0025% to 0.01% in weight activated with phosphate buffer, provides a high level disinfectant that kills all microbes that do not form spores within 10.0 minutes at room temperature, kills bacterial spores on surfaces with their culture medium in the course of 6.0 hours at room temperature, has a non-offensive, but noticeable odor and therefore can be easily avoided and can be used safely and economically with heat-sensitive equipment for up to 14 days. Therefore, the objects of the invention are achieved. The following examples are offered to further illustrate but not necessarily limit the invention. It goes without saying that the modifications to both ingredients and the ranges of additions can be made without departing from the spirit and scope of the invention. In other words, the examples are illustrative but not limiting of the scope of the invention. EXAMPLE 1 A typical formulation of this invention was mixed and is as follows: Glutaraldehyde up to 3.2% by volume Isopropanol 26% by volume Nonionic surfactant 0.01% by weight Na2HPO4 buffer pH 7.4 Acetate 8% by weight Water remaining This formulation was used for example 2. EXAMPLE 2 This example demonstrates that both alcohol, preferably isopropanol, and Acetate salts are necessary for optimal tuberculocidal activity. In this study, several formulas with and without the active ingredients isopropanol and potassium acetate were prepared and tested for their ability to kill Mycobacterium bovis vas. BCG in a suspended test of mortality rate. Five (5.0) mi of a M. bovis var. GCG containing 5% (v / v) of heat inactivated calf serum was added to 45.0 ml of a formulation of Example 1 at 20 ° C. After 2.5, 5.0, 7.5 and 10.0 minutes at 20 ° C, 1.0 ml of the reaction mixture was removed and a series of dilutions were made at the tenth power in 9 ml of neutralization recovery medium. filtered through 0.45 μ membrane filters and rinsed with sterile deionized water.

The filters were placed on M7H9 agar in Petri dishes and incubated for 3-4 weeks at 35 + 2 ° C. The colonies were counted and multiplied by the appropriate dilution factors to determine the number of surviving colony forming units ( CFU)) in the reaction flask with a given exposure. Cidex®, a commercially available material was tested in the same way with exposure times of 5.0, 1 0.0, 20.0 and 30.0 minutes at 25 ° C. In both studies, the formulation of the invention containing 2.4% glutaraldehyde, 15% isopropanol and 5% potassium acetate killed M. bovis var. BCG faster than the other formulas including Cidex®. The same formula was diluted 1.5 times to give approximately 1.6% glutaraldehyde, 1.0% isopropanol and 3.3% potassium acetate was the second fastest in killing M. bovis var. BCG The formula contains 2.4% glutaraldehyde and 15% isopropanol (without potassium acetate) mato M. bovis var. BCG slightly faster than the formula containing 2.4% glutaraldehyde and 5% potassium acetate (without isopropanol) and Cidex®. In both studies, the formulas of the invention (undiluted and diluted 1.5 times) containing isopropanol and potassium acetate had a better performance than the formulas that did not have some of those ingredients and better than Cidex®. Therefore it can be seen that isopropanol and potassium acetate are both necessary ingredients to greatly improve the killing of M. 6th s var. BCG The procedure necessary to obtain the previous conclusions in this example 2 were the following: Preparation of Mycobacterium bovis vas. BCG Mycobacterium bovis vas. Fresh BCG was obtained in a twelve month period of this test. The crops of M. bovis var. BCG were cultured on M7H9 agar plates in 25 250 mm tubes with screw caps for 21 to 25 days at 35 + 2 ° C. These were the stock cultures and were stored in the refrigerator at 3 + 2 ° C for use in a test. A culture broth was mixed in a swirl mixer and homogenized in a tissue homogenizer using 5 to 10 movements. One (1) part of calf serum inactivated with heat with heat was added to 1 9 parts of culture (a final concentration of 5% (v / v)). Preparation of Formulas of the Invention The following formulas were prepared and tested: (1) 2.4% glutaraldehyde, 15% isopropanol, 5% potassium acetate, 0.001% keyacid blue, 0.0025% Laureth-23, Q .S to 1 00 ml of distilled water. Activate with yellow # 5, NaH2PO4 and Na2H PO4 to adjust the pH to approximately 7. 60. (2) 2.4% glutaraldehyde, 1 5% isopropanol, 0.001% keyacid blue, 0.0025% Lau reth-23, Q.S to 1 00 ml distilled water (without potassium acetate). Activate with yellow # 5, NaH2PO and Na2HPO to adjust the pH to approximately 7.60. (3) 2.4% glutaraldehyde, 5% potassium acetate, 0.001% keyacid blue, 0.0025% Laureth-23, Q.S up to 100 ml distilled water (without isopropanol). Activate with yellow # 5, NaH2PO4 and Na2HPO4 to adjust the pH to approximately 7. 60. (4) 2.4% glutaraldehyde, 15% isopropanol, 5% potassium acetate, 0.001% keyacid blue, 0.0025% Laureth-23, Q.S up to 100 ml distilled water. Activate with yellow # 5, NaH2PO and Na2HPO to adjust the pH to approximately 7. 60. Dilute 2 + 1 with synthetic heavy water (1.6% glutaraldehyde, 10% isopropanol, 3.33% potassium acetate). Expose M. bovis var. BCG to formulas (1) - (4) Forty-five (45.0) mi of the selected formula was poured into a 250 ml Erlenmeyer flask and brought to a temperature of 20 + / TC in a water bath. Five (5.0) mi of a suspension of M. bovis var. BCG containing 5.0% (v / v) of heat-inactivated calf serum was added and the solution was stirred to mix. After exposure times of 2.5, 5.0, 7.5 and 10.0 minutes at 20 + 1 ° C, 1 .0 ml of the disinfectant / culture solution was removed and dilutions were made to the tenth serial power, such as 1 .0 Mi in portions of 9 ml of Dey-Engley neutralizing recovery medium containing 1% glycine. Dilutions were filtered through 0.45 μm membrane filters and rinsed with approximately 50 ml of sterile deionized water (SDIW). The filters were placed on M7H9 agar in Petri dishes. The plates were incubated for 3-4 weeks at 35 + 2 ° C inverted in an autoclave bag ventilated with water to minimize evaporation of water and dry the plates during the thin incubation period. The colonies M. bovis var. BCG were counted and multiplied by the appropriate dilution factor to determine the number of colony forming units (CFU) in the reaction flask at various times (S). In the same manner as described above, the Cidex® solution diluted at 1.5% glutaraldehyde was tested against M. bovis var. BCG using exposure times of 5, 10, 20 and 30 minutes at 25 + 1 ° C. The whole test was repeated. Validation of the Neutralization Two series of dilutions were made to the tenth power of disinfectants with a test power such as 1.0 mi in 9 ml of neutralizing recovery medium. Each dilution tube was inoculated with approximately 200 CFU of M. bovis var. BCG in a 1 .0 ml recovery broth. After 10 minutes at room temperature, the solutions were filtered through 0.45 μm membrane filters and rinsed with approximately 40 ml of SDIW. The filters were placed on M7H9 agar in Petri dishes. The plates were incubated for 3-4 weeks in an autoclave bag ventilated with air at 35 + 2 ° C. Similar numbers on all plates validated the neutralization of the disinfectant and phenol by means of the recovery process. Determination of the original number of M. bovis var. BCG in the reaction flask (So). The test culture was examined to determine the original number of CFUs in the reaction flask. Five (5.0) mi of M. bovis var. BCG were added to 45 ml of SDIW and shaken to mix. One (1.0) mi was removed and serial dilutions were made to the tenth potency in 9 ml portions of neutralizing recovery medium. Three dilution groups were made. Dilutions 3 to 6 were filtered through 0.45μm membrane filters and rinsed with approximately 50 ml of SDIW. The filters were placed on M7H9 agar in Petri dishes and incubated for 4 to 5 weeks at 35 + 2 ° C in an autoclave bag ventilated with air. The colonies of M. bovis var. BCG were counted and multiplied by means of the appropriate dilution factor to determine the number of CFUs originally in the reaction flask (So). In both studies, undiluted formulations containing 2.4 & of glutaraldehyde, 15% isopropanol and 5% potassium acetate, killed M. bovis var. BCG faster than all other formulas including Cidex®. The same formula was diluted 1.5 times to approximately 1.6% glutaraldehyde, 10% isopropanol and 3.33% potassium acetate and presented the second annihilation fastest of M. bovis var. BCG The formula containing 2.4% glutaraldehyde and 15% isopropanol (without potassium acetate) killed M. bovis var. BCG slightly faster than the formula containing 2.4% glutaraldehyde and 5% potassium acetate (without isopropanol) and Cidex®. EXAMPLE 3 This example shows a test to measure the relative concentrations of glutaraldehyde in the upper air (vapors) for several glutaraldehyde (GA) test solutions. Equal volumes of 1 .0 L of 1) 1 .0, 2.0 and 2.5% GA in water, 2) 1 .0, 2.0 and 2.5% GA plus 25% IPA in water, 3) Cidex® activated dialdehyde solution (2.5% GA), 4) the invention (3.0% GA + 25% IPA plus 8% acetate) and 5) IV formulation (2.5% GA + 20% I PA plus 8% acetate) were placed in the bottom of 5.0 gallon glass jars. The jars were capped and the lids had two different sizes of glass tubes connected the longer glass tube to an air pump, and the shorter glass tube connected to a porous stone in a MBTH solution. After 1 hour of saturation with air, a constant volume of air is pumped through the upper space of the glass jar, trapped in a 50.0 ml solution of 0.5% 3-methyl-2-benzothiazolinone (MBTH). it was kept for 5.0 minutes, 20.0 ml of 1.75% oxidant (iron chloride hexahydrate and sulfamic acid) was added, maintained for 1.0 hour, and the resulting color was measured with respect to absorbency. GA reacted with these solutions to return various intensities of green / blue as a function of GA concentration. The measurements were compared directly and to a standard curve to determine the concentration of GA in the air (vapors) released by the 1.0 L of various test solutions. The results showed vapor suppressions when the acetate was present. The glutaraldehyde vapors released from various formulations of the present invention in which alcohol and acetate were present were consistently lower than the Cidex® solution. For example the glutaraldehyde vapors released from the formulation that nominally contained 3% glutaraldehyde, 25% isopropanol alcohol and 8% potassium acetate and the formulation that nominally contained 2-5% glutaraldehyde, 20% alcohol isopropanol and 8% potassium acetate were released 65-80% and 78-85% lower than the glutaraldehyde vapors released by Cidex® (2.5% glutaraldehyde) respectively. This study therefore demonstrates that there are far fewer glutaraldehyde fumes of the invention (glutaraldehyde + isopropanol + acetate salts) than from Cidex® (glutaraldehyde only). There are also similar levels of glutaraldehyde smoke from glutaraldehyde alone. glutaraldehyde + isopropanol. The conclusion is that the acetate salts somehow suppress the glutaraldehyde fumes. The above data and the conclusions reached make it clear that the invention achieves at least all of its primary objectives.

Claims (7)

1. CLAIMS 1. A water-based aqueous solution for disinfecting and / or sterilizing at room temperature with low vapor production having an activated pH of about 7.3 to about 7.9 which contains: from about 2.0% to 5.0% glutaraldehyde by volume; from about 4.0% to about 26.0% by volume of alcohol, wherein the alcohol is selected from the group consisting of methanol, ethanol and isopropanol; an effective amount of a buffer compatible with glutaraldehyde; and an acetate salt in from about 3% by weight to about 8% by weight.
2. 2. An aqueous disinfectant and / or sterilizing solution according to claim 1, wherein the alcohol concentration is from 24% to about 26% by volume.
3. 3. An aqueous disinfectant and / or sterilizing solution according to claim 1, wherein the buffer is phosphate buffer.
4. 4. An aqueous disinfectant and / or sterilizing solution according to claim 1, further including a surfactant selected from the group consisting of nonionic, cationic and anionic surfactants at a level of 0.0025% to 0.01% by weight.
5. 5. An aqueous disinfectant and / or sterilizing solution according to claim 4, wherein the surfactant is a non-ionic surfactant.
6. 6. A method for improving the potency and reducing the fumes of the water-based disinfectant and / or sterilizing aqueous solution, which consists of: using a straight or branched chain lower alcohol solution at a concentration of about 5% to about 26% by volume in combination with 3% by weight to 8% by weight of an acetate salt. 7. A disinfectant kit comprising: a first container of storable solution that is stable for up to 12 months containing from about 2% to about 5% of glutaraldehyde by volume; from about 4% to about 26% by volume of alcohol, wherein the alcohol is selected from the group consisting of methanol, ethanol and isopropanol; an effective amount of a buffer compatible with glutaraldehyde; and an acetate salt in from about 3% by weight to about 8% by weight; a second container of phosphate buffer in an amount sufficient to provide a concentration of 4 g / l per liter at 7 g / l per liter, and provide a pH when combined with the first container of from 7.3 to 7.9; and instructions for mixing the first and second containers to provide a working disinfectant solution that is stable for up to 14 days. 8. An aqueous disinfectant and / or sterilizing solution according to claim 2, wherein the amount of acetate salt amounts to about 8% by weight. 9. A disinfectant kit comprising: a first container of storable solution that is stable for up to 12 months containing from about 2% to about 5% of glutaraldehyde by volume; from about 24% to about 26% by volume of alcohol, wherein the alcohol is selected from the group consisting of methanol, ethanol and isopropanol; an effective amount of a buffer compatible with glutaraldehyde; and an acetate salt in about 8% by weight; a second container of phosphate buffer in an amount sufficient to provide a concentration of 4 g / l per liter at 7 g / l per liter, and provide a pH when combined with the first container of from 7.3 to
7. 7.9; and instructions for mixing the first and second containers to provide a working disinfectant solution that is stable for up to 14 days.