Patent Application
20230151303
A wipe impregnated with a chemistry solution is capable of achieving intermediate level disinfection within a short contact time and is capable of cleaning dried on soils. The wipe substrate is absorbent enough to hold and deliver sufficient liquid to thoroughly wet even large devices for the duration of the contact time but the wipe substrate does not absorb the active ingredients. The chemistry is specifically formulated with a moderate pH range of from about 8.5 to about 10.5.
Healthcare customers working in the Central Services (CS) department are responsible for the reprocessing of the many instruments used in a healthcare setting. These instruments are received on the dirty side of the CS where they must be cleaned and disinfected before being delivered to the clean side of the CS for further processing. Typically, dirty instruments are placed in Washer/Disinfectors to go through cycles that include a cleaning phase to remove soil and a thermal rinse phase to provide intermediate level disinfection. These steps render the instrument clean and safe to handle on the clean side of the CS.
However, there are a number of heat-liable, non-submersible instruments that would be damaged by the conditions of conventional Washer/Disinfectors. These instruments must be cleaned by hand and then passed from the dirty side of the CS to the clean side through a pass-through window. This creates a need for a cleaner/disinfectant solution that is designed for use on medical devices to provide intermediate level disinfection.
Some of the currently marketed disinfectant wipe products are not one-step cleaner/disinfectors. There are many different wipe products available, but these products are not specifically labelled for use on non-submersible/heat liable medical devices. Additionally, various currently marketed products have a high pH such as from about 11.0 to about 12.5 which can negatively impact the safety profile for the user as well as the compatibility profile of the product with substrates common to medical devices.
The cleaner/disinfectant composition of the present invention has been formulated to be used for pass-through items in a Central Services department of hospitals. The formulation is designed to render instruments safe to handle on the clean side of the Central Services department. The wipe is impregnated with a chemistry solution that is capable of achieving intermediate level disinfection claims within a three-minute contact time and capable of cleaning dried on soils. Furthermore, the wipes of the present invention have the following advantages. It contains a mixture of quaternary ammonium chloride compounds of various chain lengths that allow for a broad spectrum of microbial disinfection; an alcohol co-solvent that confers broader efficacy profile and improves bioavailability of the quaternary ammonium active ingredient; an ether alcohol to enhance the antimicrobial efficacy of the product against mycobacteria; and wetting agents comprising a polyethylene glycol derivative of Cocamine having a high and low HLB value that improve the solubilization/removal of diverse soil types.
In general, a cleaner, disinfectant composition comprises a quaternary ammonium chloride disinfectant in an amount of from about 0.5 to about 3.0 wt. %; an ether alcohol comprising PPG-2 methyl ether, propylene glycol methyl ether acetate, dipropylene glycol dimethyl ether, propylene glycol phenyl ether, propylene glycol n-propyl ether, or butoxydiglycol, or any combination thereof, in an amount of from about 1.0 to about 5.0 wt. %; a wetting agent comprising ethoxylated alcohols and ethoxylated amines, independently, having from 1 to about 4 ethoxyl groups, amine oxides, block copolymers such as block copolymers of propylene oxide and ethylene oxide (20% EO), sorbitan esters, methyl esters, and PEG-2 Cocamine, or any combination thereof, having an HLB value of from about 4 to about 10 in an amount of from about 0.5 to about 3.0 wt. %; a wetting agent comprising ethoxylated alcohols and ethoxylated amines, independently, having from 7 to about 20 ethoxyl groups, ethoxylated amines, amine oxides, block copolymers such as block copolymers of propylene oxide and ethylene oxide (50% EO) polyoxyethylenated alcohol, sorbitan esters, methyl esters, and PEG-15 Cocamine, or any combination thereof, having a high HLB value of from about 11 to about 17 in an amount of from about 0.1 to about 1.0 wt. %; a short chain aliphatic alcohol having from 1 to about 3 carbon atoms in an amount of from about 35 to about 55 wt. %, and wherein the remainder is an amount of H2 that adds up to 100 wt. %.
The ready-to-use wipes of the present invention allow for a one-step cleaning and intermediate level disinfection of heat-liable, non-submersible medical devices, generally prior to passing these instruments to the clean side of a Central Services department of a hospital, or other medical care institution or medical instrument supply company. The wipes are absorbent enough to hold and deliver sufficient liquid to thoroughly wet even large devices for the duration of the contact time and the wipe per se does not absorb any active ingredients. These and other advantages will become apparent from the following detailed description of the preparation of the ready-to-use cleaner/disinfectant wipes of the present invention.
The composition or formulation of the present invention is generally a finely tuned system of several components such as active disinfection compounds, a short chain aliphatic alcohol that boosts the efficacy profile against organisms, an alkalinity source, an ether alcohol that enhances the antimicrobial efficacy of the product against mycobacteria, wetting agents and cleaning profile compounds, as well as a pH adjuster.
Hereinafter, numerous compounds are set forth that comprise the formulation of the ready to use cleaner/disinfectant wipe product of the present invention. With respect to the various chemical compounds, the amount thereof is given in wt. % with the same of each individual compound being based upon 100 wt. %, or 100 parts by weight of the total composition formulation. Any active amount of a particular compound refers to the weight percent of active ingredient within the compound per se, that is the actual given weight percent of a compound utilized in the formulation of the present invention.
A suitable disinfect is various quaternary ammonium chlorides that are well known to the art and to the literature. A particularly useful active ingredient ammonium compound is a mixture by weight, of four quaternary ammonium chlorides as follows: 20% alkyl (C14 50%, C12 40%, C16 10%) dimethyl benzyl ammonium chloride, 15% octyl decyl dimethyl ammonium chloride, 6% dioctyl dimethyl ammonium chloride and 9% didecyl dimethyl ammonium chloride. This disinfectant has an active compound content of approximately 50% to 52% by weight and also contains approximately 10% by weight of ethyl alcohol with the remainder being water. This material is commercially available as Bardac 205M, manufactured by Lonza of Basel, Switzerland. It is EPA registered with respect to being a suitable hard surface disinfectant. In addition to these compounds, other suitable quaternary ammonium compounds include n-alkyl dimethyl ethylbenzyl ammonium chloride, n-akyl trimethyl ammonium chloride, dimethyloctadecyl[3-(trimethyoxsilylpropyl) ammonium chloride, or polymeric quaternary ammonium chlorides, or any combination thereof.
The total amount of the one or more quaternary compounds that is utilized in the present invention is generally from about 0.5 wt. % to about 3.0 wt. %, desirably from about 0.7 wt. % to about 2.5 wt. %, and preferably from about 0.8 wt. % to about 2.2 wt. %.
Another compound of the present cleaner/disinfectant wipe for intermediate level disinfection comprises a short chain aliphatic alcohol having from about 1 to about 3 carbon atoms such as methyl alcohol, ethyl alcohol, propyl alcohol, or isopropyl alcohol, wherein isopropyl alcohol is preferred, or any combination thereof. The purpose of the alcohol is to increase the efficacy profile of the wipe against certain organisms as well as improve the chemical and physical stability of the formulation. The alcohol is generally utilized in large amounts such as from about 35 to about 55 wt. %, desirably from about 40 to about 50 wt. %, and preferably from about 42 to about 48 wt. %. The alcohol is considered an active component of the wipe formulation or composition and generally exists in the noted high active amounts thereof, such as about 100 wt. %.
Optionally, but desirably, one or more alkalinity sources is utilized to boost the buffering capacity of the formulation in amounts of such as from about 0.1 to about 2.0 wt. %, desirably from about 0.2 to about 1.5 wt. %, and preferably from about 0.3 to about 1.0 wt %. Examples of suitable alkalinity compounds include monoethanol amine, triethanol amine, potassium hydroxide, sodium hydroxide, calcium carbonate/bicarbonate, sodium carbonate/bicarbonate, 2-amino-2-methyl-1-propanol, or monoisopropanolamine, wherein monoisopropanolamine is preferred, or any combination thereof. Amounts in excess of the broad noted range generally caused the product to be outside the optimal pH range which can negatively impact the overall safety profile and compatibility profile of the product.
Another component of the cleaner/disinfectant wipe formulation of the present invention is an ether alcohol that enhances the antimicrobial efficacy of the product against mycobacteria. Suitable compounds include PPG-2 methyl ether, propylene glycol methyl ether acetate, dipropylene glycol dimethyl ether, propylene glycol phenyl ether, or propylene glycol n-propyl ether, wherein butoxydiglycol is preferred, or any combination thereof. Suitable amounts thereof generally range from about 1.0 to about 5.0 wt. %, desirably from about 2.5 to about 4.0 wt %, and preferably from about 3.0 to about 3.5 wt. %. An excess of this material outside of the above ranges generally negatively impacts the products compatibility profile whereas an undercharge thereof will negatively impact the product's antimicrobial efficacy profile.
Wetting agents are desired since they contribute to the wetting and cleaning profile of the product. Suitable wetting agents generally have a high HLB (hydrophilic-lipophilic balance) of from about 11 to about 17 and preferably from about 14 to about 16. Such compounds include ethoxylated alcohols and ethoxylated amines, independently, having 7 to 20 and preferably from 9 to 15 ethoxyl groups, amine oxides such as Lauramine oxide and Cocamidopropyl amine oxide, block copolymers such as block copolymers of propylene oxide and ethylene oxide (50% EO), Poloxamer 235, Poloxamer 184, Meroxapol 105, Meroxapol 174, polyoxyethylenated alcohol (C9-11 Pareth 8), sorbitan esters, methyl esters, and PEG-15 Cocamine, or any combination thereof. A preferred high HLB wetting agent is PEG-15 Cocamine. Suitable amounts thereof generally range from about 0.1 to about 1.0 wt %, desirably from about 0.1 to about 0.5 wt. %, and preferably from about 0.2 to about 0.4 wt. %. A significant undercharge can negatively impact the product's cleaning performance against polar soils. Moreover, it is noted that significant overcharges or undercharges can negatively impact the antimicrobial efficacy profile.
Another wetting agent that has a moderately low HLB (hydrophilic-lipophilic balance) are various compounds such as ethoxylated alcohols and ethoxylated amines, independently, having from 1 to 4 ethoxy groups, amine oxides such as Stearamine oxide, block copolymers propylene oxide and ethylene oxide (20% EO), Poloxamer 182, Poloxamer 101, Meroxapol 172, Meroxapol 252, polyether polyols, sorbitan esters, and methyl esters and the like with HLBs from about 4 to about 10, and desirably from 5 to about 7, or any combination thereof. A preferred low HLB compound is PEG-2 Cocamine. Suitable amounts thereof generally range from about 0.5 to about 3.0 wt. %, desirably from about 1.0 to about 2.0 wt. %, and preferably from about 1.2 to about 1.8 wt. %. Similar to the PEG-15 Cocamine, a significant undercharge can impact the product negatively with respect to cleaning performance thereof against non-polar soils. Moreover, overcharges or undercharges can also negatively impact the antimicrobial efficiency thereof.
With regard to the pH adjuster, generally many different types of pH adjusters can be utilized such as phosphoric acid, hydrocholoric acid, glycolic acid, oxalic acid, lactic acid, formic acid, and the like, or any combination thereof. A preferred pH adjuster is citric acid which can be supplied either in liquid form or as a 100% active solid powder. General amounts thereof are from about 0.025 to about 0.500 wt. %, desirably from about 0.050 to about 0.300 wt. %, and preferably from about 0.100 to about 0.25 wt. %. Significant overcharge of this material can cause a pH to be too low and thus negatively impact the product's antimicrobial efficacy profile. Moreover, undercharges can also cause the product pH to be elevated which can result in damage to delicate instrumentation and negatively impact the safety profile.
The remaining portion of the above-noted compounds that comprise Formula 1 of the present application is Deionized water as in an amount that add up to a total 100% or 100 total parts by weight, typically about 47.26 wt. % or parts by weight. However, in another embodiment, i.e. Formula 2 as set forth hereinbelow, hexylene glycol can be partially substituted for water, or a cosolvent in various suitable amounts such as approximately 7.5 wt. %.
With respect to the wipes, the one step cleaner disinfectant solution is saturated thereon to increase the ease of use of the product. The wipes are made of a non-cellulose based substrate to ensure the quaternary ammonium active ingredient is not adsorbed to the wipe. Examples of suitable materials of construction for the wipe are polyester, polypropylene, polyurethane, or similar materials, or any combination thereof, and the like. Additionally, the wipe substrate is manufactured to be 35 to 50 grams per square inch with an aperture pattern that allows for increased surface area. The higher weight of the wipe along with the aperture pattern helps to increase the amount of liquid the wipe can deliver. Alternatively, the disinfectant solution can be used to saturate a sponge made of non-cellulose material. Examples of suitable sponge materials of construction are polyester, polypropylene, or polyurethane, or similar materials, or any combination thereof, and the like.
The following formulations are preferred formulations of the various compounds of the present invention and it is to be understood that many variations thereof are also suitable.
Preferred wipe cleaner/disinfectant formulation
The above invention will be better understood by reference to the following examples which serve to illustrate the present invention but not to limit the scope thereof.
Cleaning study
A blood/protein-based soil was applied into stainless steel coupons and allowed to dry at 50° C. for 1 hour. The coupons with dried soil were removed from the oven and allowed to cool to room temperature. Once cooled, the coupons were wiped with wipes saturated in the present invention or a commercially available competitive product. The amount of time required to completely remove the dried-on soil was recorded for three replicates. The results are reported as an average of the replicates. From the data it can be seen that Formula 1 was able to remove the soil more quickly than the currently available products. This is due to the superior surfactant system present in Formula 1
The test method with regard to bacteria/fungal was according to AOAC official Method 961.02 whereas the virus testing was according to ASTM international test method designated E1053-20. M. Bovis according to AOAC official Method 965.12.
P. aeruginosa/S. aureus: All Lots = No Growth; passed
T. interdigitale: All Lots = No Growth; passed
S. epidermidis: All Lots = No Growth; passed
E. cloacae: All Lots = No Growth; passed
S. marcescens: All Lots = No Growth; passed
M. yunnanensis: All Lots = No Growth; passed
B. cepcia: All Lots = No Growth; passed
S. pyogenes: All Lots = No Growth; passed
L. monocytogenes: All Lots = No Growth; passed
C. albicans: All Lots = No Growth; passed
Antimicrobial efficacy testing was conducted with Formula 1 by an independent, third-party testing laboratory. This testing was performed to establish the efficacy profile of Formula 1 over a broad spectrum of organisms included in the mycobacterium, gram-negative/gram-positive bacteria, fungi, and virus classes. All studies were performed under GLP using test methods recognized by the US Environmental Protection Agency (EPA) which certifies disinfectant products. The bactericidal/fungicidal testing was conducted according to AOAC official Method 961.02 whereas the viricidal testing was performed according to ASTM international test method designated E1053-20. The testing for the mycobacterium species was done according to AOAC official Method 965.12. From the testing result in Table 3, it is apparent that Formula 1 has the efficacy profile of an intermediate level disinfectant.
Efficacy against M. terrae
Efficacy testing was conducted against commercially available products using Mycobacterium terrae as a surrogate for Mycobacterium bovis (target organisms for intermediate level disinfection claims.). Formula 1 was tested at its EPA Lowest Certified Limit (LCL) for each active ingredient.
Glass Slides inoculated with M. terrea under 5% organic soil conditions were wiped with the indicated product and allowed to dwell for the products label indicated contact time. After the contact time, the slides were placed in a neutralizer solution to quench the active ingredients. The neutralizer solution was filtered through a 0.2 μm filter which was incubated for 14 days at 37° C. The number of colonies present on the filters were counted. To Numerous To Count (TNTC) Designation for filters with greater than 200 Colony Forming Units (CFU).
Formula 1 shows no to low counts for each slide whereas the commercially available products show greater than 200 CFU on all or most of the slides. Formula 1 even outperforms the competitive products with longer contact times suggesting an overall superior efficacy profile.
Compatibility Testing
Compatibility testing was conducted with each substrate coupon exposed to the indicated solution under static conditions for one week at room temperature. Upon completion of the study, the wipe was removed, the coupon rinsed, and then observed for visual changes. The coupons exposed to Formula 1 and Formula 2 show no visual changes as compared to the coupons exposed to the commercially available wipe solution which caused visual damage to all three soft metals.
While in accordance with the Patent Statutes, the best mode and preferred embodiments have been set forth, the scope of the invention is not limited thereto, but rather, by the scope of the attached claims.
