COMPOSITIONS FOR MEDICAL INSTRUMENT CLEANING

Abstract

Disclosed herein are compositions comprising a nonionic surfactant and one or more inherently stable subtilisin, and methods related to the use of such compositions for the cleaning of medical and dental instruments.

Claims

1. A medical or dental instrument detergent composition comprising: between about 1% to 15% by weight of a nonionic surfactant; between about 250 ppm and about 10000 ppm of an inherently stable subtilisin variant wherein the composition does not comprise a substantial amount of a protease stabilizer.

2. The detergent composition of claim 1, wherein the composition comprises less than about 0.01% by weight, of a protease stabilizer.

3. The detergent composition of claim 2, wherein the composition comprises less than about 0.001% by weight of a protease stabilizer.

4. The detergent composition of claim 1, wherein the composition does not comprise a protease stabilizer selected from the group consisting of a protease inhibitor, peptide aldehyde, an organoboron compound, or boronic acid derivative.

5. The detergent composition of claim 4, wherein the boronic acid derivative is phenyl boronic acid (PBA) or 4-formylphenyl-boronic acid (FPBA).

6. The detergent composition of claim 1, wherein the nonionic surfactant is a C.sub.6 to C.sub.20 alcohol ethoxylate with 2 to 14 moles of ethoxylation.

7. The detergent composition of claim 6, wherein the nonionic surfactant is selected from the group of polyoxyalkylene alkyl ethers, polyalkylene glycols, alkylamine oxides, polyoxyalkylene, alkyl phenyl ethers, fatty acid polyoxyethylene esters, fatty acid sorbitan esters, fatty acids polyoxyalkylene sorbitan esters, fatty acid saccharide esters, alkyl polysaccharides, alkyl glyceryl ethers, and fatty acid alkanolamides.

8. The detergent composition of claim 1, wherein the composition further comprises between about 10-30% by weight of at least one organic solvent.

9. The detergent composition of claim 8, wherein the solvent is selected from the group consisting of polyols such as glycerol, propane-1,2-diol or propane-1,3-diol.

10. The detergent composition of claim 1, wherein the composition further comprises, from about 10% to 30% by weight of a biodegradable chelating agent.

11. The detergent composition of claim 11, wherein the biodegradable chelating agent is selected from the group of sodium salts of glutamic acid diacetic acid (GLDA), methylglycinediacetic acid (MGDA), and itaconic acid.

12. A method for cleaning a medical or dental instrument comprising: a) contacting the medical or dental instrument in a detergent for medical or dental instrument cleaning comprising between about 1% to 15% by weight of a nonionic surfactant; between about 250 ppm and about 10000 ppm of an inherently stable subtilisin variant; wherein the composition does not comprise a substantial amount of a protease stabilizer; b) allowing the instrument to be contacted for a period of time sufficient to reduce or remove soils on the instrument; and c) optionally rinsing the instrument.

13. The method of claim 12, wherein the instrument is contacted with the detergent for at least 1 minute.

14. The method of claim 13, wherein the instrument is contact with the detergent for an amount of time up to 24 hours.

15. The method of claim 12, wherein the instrument is contacted with the detergent for between a time of 1-60 minutes?

16. The method of claim 12, wherein the instrument is contacted with the detergent at a temperature between 30 degrees and 70 degrees Celsius.

17. The method of claim 16, wherein the instrument is contacted with the detergent at a temperature between 40 degrees and 60 degrees Celsius.

18. The method of claim 12, wherein the composition comprises less than about 0.01% by weight, of a protease stabilizer.

19. The method of claim 18, wherein the composition comprises less than about 0.001% by weight, of a protease stabilizer.

20. The method of claim 12, wherein the composition does not comprise a protease stabilizer selected from the group consisting of a peptide aldehyde, organoboronic acid, or boronic derivative.

21. The method of claim 20, wherein the boronic acid derivative is phenyl boronic acid (PBA) or 4-formylphenyl-boronic acid (4-FPBA).

22. The method of claim 12, wherein the nonionic surfactant is a C6 to C20 alcohol ethoxylate with 2 to 14 moles of ethoxylation.

23. The method of claim 22, wherein the nonionic surfactant is selected from the group of polyoxyalkylene alkyl ethers, polyalkylene glycols, alkylamine oxides, polyoxyalkylene alkyl phenyl ethers, fatty acid polyoxyethylene esters, fatty acid sorbitan esters, fatty acids polyoxyalkylene sorbitan esters, fatty acid saccharide esters, alkyl polysaccharides, alkyl glyceryl ethers, and fatty acid alkanolamides. an alcohol ethoxylate.

24. The method of claim 12, wherein the composition further comprises between about 10-30% by weight of at least one organic solvent.

25. The method of claim 24, wherein the solvent is selected from the group consisting of propylene glycol, glycerol, propane-1,2-diol or propane-1,3-diol.

26. The method of claim 12, wherein the composition further comprises, from about 10% to 30% by weight of a biodegradable chelating agent.

27. The detergent composition of claim 26, wherein the biodegradable chelating agent is selected from the group of sodium salts of glutamic acid diacetic acid (GLDA), methylglycinediacetic acid (MGDA), and itaconic acid.

Description

EXAMPLES

Example 1

Method for Establishing Washing Performance Using TOSI Cleaning Indicator

[0053] The TOSI cleaning indicator is a blood soil comprising a mixture of different sources of protein applied on stainless steel. The stainless-steel coupon is placed in a see-through plastic holder and submerged into a beaker with a wash solution. The beaker is placed in a water bath at 50° C. and stirred at 300 rpm for 20 minutes. The pH of the wash solution was determined by the detergent formula used.

[0054] The cleaning performance was determined by using multispectral image acquisition using a VideometerLab4 (Videometer A/S, Hørsholm, Denmark). The imaging software allows to calculate the surface area of the blood soil that is still present on the stainless-steel surface, and compare to the initial surface before washing.

[0055] A commercially available detergent for medical instrument cleaning containing protease, Prolystica 2X Concentrate Enzymatic (ex. Steris), was purchased to evaluate the washing performance according to above mentioned methodology. Part of the detergent was incubated at 90° C. for 20 minutes to inactivate the protease; after cooling down to ambient temperature three (3) different proteases were dosed at equal inclusion level.

[0056] The washing performance on a TOSI cleaning indicator is summarized in below table. The detergent was dosed at 1 g/L.

TABLE-US-00001 Soil Detergent removal Prolystica 2X Concentrate Enzymatic 75% ex Steris Steris detergent (inactivated) − no protease   8.8% Steris detergent (inactivated) + 0.1 g/L 94% Commercial protease 1) Steris detergent (inactivated) + 0.1 g/L 84% Commercial protease with stabilizer 2) Steris detergent (inactivated) + 0.1 g/L 81% stable protease variant 1 3) 1) PREFERENZ ® P 200 2) Liquanase Evens 900L (ex. Novozymes) 3) Subtilisin variant 1 (SQCBV419, WO2017210295)

[0057] The percentage of soil removal (Soil removal %) is defined as the surface area after washing divided by the initial surface area. Each experiment was run in duplicate. The measurement data show that all three proteases in this study meet or exceed the washing performance of the commercial product at 0.1 g/L. Only a low level of soil removal is obtained by the inactivated detergent sample without protease.

Example 2

Compositions for Medical Instrument Cleaning Detergent and Protease Biochemical Stability

[0058]

TABLE-US-00002 Ingredients Formula A Formula B C12-14 Alcohol Ethoxylate, 9EO 8 2 Mono propylene glycol 5 20 Glycerol 10 10 Ethanolamine 1 1 Sodium citrate 3 3 CMIT/MIT 1) 0.01 0.01 Protease 2) 2000 ppm 2000 ppm Amylase 3)  250 ppm  250 ppm Lipase 4) 1200 ppm 1200 ppm Water Balance Balance pH 7.8-8.0 7.8-8.0 Inclusion level is given “as is” in weight % except for enzymes (active enzyme protein in ppm) 1) Kathon LX 150 ex DOW 2) Subtilisin variant 1 (SQCBV419, WO2017210295) 3) PREFERENZ ® S210 4) PREFERENZ ® L 100

[0059] The residual protease activity was tested by measuring the hydrolysis of N-suc-AAPF-pNA substrate (or AAPF method as described in WO2017210295) after incubation of the detergent sample for 2 & 4 weeks at 37° C. The residual protease activity was divided by the initial activity and expressed in percentage.

TABLE-US-00003 Formula A Formula B T = 2 T = 4 T = 2 T = 4 weeks weeks weeks weeks Standard protease 1) 19%  8% 50% 30% Protease with stabilizer 2) 85% 75% 84% 74% Stable protease variant 1 3) 80% 60% 97% 92% Stable protease variant 2 4) 90% 75% 90% 89% Stable protease variant 3 5) 59% 41% 88% 83% 1) PREFERENZ ® P 200 2) Liquanase Evens 900L ( Novozymes) 3) Subtilisin variant 1 (SQCBV419, WO2017210295) 4) Subtilisin variant 2 (Blcarl 07865, U.S. Provisional Application 62/591976, filed Nov. 29, 2017) 5) Subtilisin variant 3 (SQCBV35, WO2017210295)

[0060] The data demonstrate that a commercial protease has low residual activity when stored for 4 weeks storage at 37° C. due to the absence of a protease stabilizer, particularly when dosed in Formula A. Using a commercial protease with a peptide aldehyde stabilizer a residual stability of 75% or 74%, respectively, can be achieved. For Formula A, stable protease variant 2 can achieve the same stability profile, while each stable protease variant can retain even more stability in Formula B in the absence of a protease stabilizer.

[0061] Although the disclosure has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.

[0062] All publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present disclosure. To the extent that section headings are used, they should not be construed as necessarily limiting.