ANTIMICROBIAL AND ANTIVIRAL COMPOSITE POLYMER SURFACES

Abstract

The present invention relates to composite polymer surfaces which are endowed with antimicrobial and antiviral properties. In the present invention, polymer composites containing additives are obtained, wherein combinations (comprising at least two or more substances) of boron compounds and/or zinc pyrithione made with chlorhexidine gluconate and/or triclosan are used. The invention enables to prevent biodegradation or biocontamination occurring on surfaces. The invention is for controlling the pathogen factors (bacteria, yeasts, fungi and viruses), which are the causes for surface-borne hygiene, allergy and infectious diseases, in sectors (particularly agriculture, health, food and defense) where polymer composites are widely used.

Claims

1-9. (canceled)

10. A composite polymer surface comprising: zinc pyrithione, boron compound and polymer granules.

11. The composite polymer surface of claim 10 further comprises triclosan.

12. The composite polymer surface of claim 11, wherein the boron compound is sodium borate.

13. The composite polymer surface of claim 12, wherein the mass ratio of zinc pyrithione is 2.5%, the mass ratio of sodium borate is 10%, and the mass ratio of triclosan is 0.2%.

14. The composite polymer surface of claim 10, wherein the boron compound is disodium octaborate tetrahydrate.

15. The composite polymer surface of claim 14, wherein the mass ratio of zinc pyrithione is 3%, and the mass ratio of disodium octaborate tetrahydrate is 3%.

16. A composite polymer surface comprising sodium borate, chlorhexidine gluconate and polymer granules.

17. The composite polymer surface of claim 16, wherein the mass ratio of sodium borate is 15% and the mass ratio of chlorhexidine gluconate is 2%.

18. A composite polymer surface comprising zinc pyrithione, triclosan and polymer granules.

19. The composite polymer surface of claim 18, wherein the mass ratio of zinc pyrithione is 3% and the mass ratio of by mass of triclosan is 0.2%.

20. The composite polymer surface of claim 10, wherein the polymer granules are made of one or more materials selected from the group consisting of polypropylene, polyester, polystyrene, polyamide, polyoxymethylene, polyethylene terephthalate, polycarbonate, polymethylmethacrylate, polydimethylsiloxane, polytetrafloroethylene, polyether ketone, acrylonitrile butadiene styrene, thermoplastic elastomer, styrene acrylonitrile, polylaktide, polyvinylchloride, polypropylene, polyethylene and polyurethane.

21. The composite polymer surface of claim 16, wherein the polymer granules are made of one or more materials selected from the group consisting of polypropylene, polyester, polystyrene, polyamide, polyoxymethylene, polyethylene terephthalate, polycarbonate, polymethylmethacrylate, polydimethylsiloxane, polytetrafloroethylene, polyether ketone, acrylonitrile butadiene styrene, thermoplastic elastomer, styrene acrylonitrile, polylaktide, polyvinylchloride, polypropylene, polyethylene and polyurethane.

22. The composite polymer surface of claim 18, wherein the polymer granules are made of one or more materials selected from the group consisting of polypropylene, polyester, polystyrene, polyamide, polyoxymethylene, polyethylene terephthalate, polycarbonate, polymethylmethacrylate, polydimethylsiloxane, polytetrafloroethylene, polyether ketone, acrylonitrile butadiene styrene, thermoplastic elastomer, styrene acrylonitrile, polylaktide, polyvinylchloride, polypropylene, polyethylene and polyurethane.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Antimicrobial and antiviral composite polymer surfaces developed to fulfill the objectives of the present invention are illustrated in the accompanying figures, and the details of these figures are listed below

[0025] The abbreviations used in the experimental studies are as follows: Zinc Pyrithione ZP, Triclosan T, Disodium octaborate tetrahydrate DOP, Sodium borate SB.

[0026] FIG. 1 is the view of the activity of PVC surfaces containing [0027] 1: 2.5% ZP, 10% SB and 0.2% T, [0028] 2: 3% ZP and 3% DOT, [0029] 3: 3% ZP and 0.2% T, [0030] 4: 15% SB, 2% CH against MRSA.

[0031] FIG. 2 is the view of the activity of PVC surfaces numbered 1, 2, 3 and 4 against Aspergillus niger.

[0032] FIG. 3-a is the view obtained as a result of washing PU surface which is contaminated with Aspergillus niger without any additives and performing regressive isolation via serial dilution method. [0033] b. is the view obtained as a result of washing PU surface which is contaminated with Aspergillus niger containing 3% ZP and 0.2% T, and performing regressive isolation via serial dilution method.

[0034] FIG. 4-a is the view obtained as a result of washing PU surface which is contaminated with Candida albicans without any additives and performing regressive isolation via serial dilution method. [0035] b. is the view obtained as a result of washing PU surface which is contaminated with Candida albicans containing 3% ZP and 0.2% T, and performing regressive isolation via serial dilution method.

DETAILED DESCRIPTION OF THE INVENTION

Experimental Studies

[0036] In the embodiment of the invention, composite polymer surfaces are obtained by mixing boron compounds and zinc pyrithione separately or in combination together with different concentrations and combinations of chlorhexidine gluconate and/or triclosan with polymer granules.

[0037] In the present invention; one of zinc borate, sodium borate, sodium perborate tetrahydrate, borax pentahydrate; and preferably disodium octaborate tetrahydrate is selected as the boron compound.

Antimicrobial Tests

Modified Disc Diffusion Method

[0038] Standard NCCLS disc diffusion method (Lalitha and Vellore, 2005) was used upon being modified in order to determine the antimicrobial activity of boron compounds on each microorganism that is being tested. The 100 l solution including 10.sup.8 cfu/ml bacteria, 10.sup.6 cfu/ml yeast and 10.sup.4 spore/ml fungi was prepared with new cultures and inoculated with spreading method on Nutrient Agar (NA), Sabouraud Dextrose Agar (SDA) and Potato Dextrose Agar (PDA), respectively. 20 l of sterile water was dropped on the empty discs and it was separately immersed into pulverized zinc borate, sodium borate, sodium perborate tetrahydrate, borax pentahydrate, disodium octaborate tetrahydrate. The discs coded with zinc borate, sodium borate, sodium perborate tetrahydrate, borax pentahydrate, disodium octaborate tetrahydrate were placed in inoculated petri dishes. Empty discs with 20 l drop of sterile water were used as negative control. Ofloxacin (10 g/disc) and nystatin (30 g/disc) were used as positive control groups for bacteria and fungi, respectively. The petri dishes, which were inoculated and on which modified disc diffusion method was applied, were kept at 361 C. for bacteria for 24 hours and for yeasts for 48 hours and at 251 C. for fungi for 72 hours. Antimicrobial activity against microorganisms tested with modified disc diffusion method was assessed by measuring the inhibition zone (area where microorganisms do not grow). Antimicrobial activity test results of the tested boron compounds are summarized in Table 1. All tests were repeated at least twice.

Embodiment 1

[0039] For 100 g antimicrobial and antiviral polyvinyl chloride (PVC) composite material; 5 g zinc pyrithione was added from the side powder feeder when 95 g PVC granules were passing through the twin screw extruder at 150 C. and thus PVC composite granules comprising 5% active ingredient were obtained. Then, cold press was applied to PVC composites which were melted at 100-180 C. thereby obtaining antimicrobial and antiviral surfaces. The said obtained surfaces were subjected to antimicrobial activity tests.

Embodiment 2

[0040] For 100 g antimicrobial and antiviral PVC composite material; 5 g zinc pyrithione and 5 g disodium octaborate tetrahydrate were added from the side powder feeder when 90 g PVC granules were passing through the twin screw extruder at 150 C. and thus PVC composite granules comprising 5% active ingredient were obtained. Then, cold press was applied to PVC composites which were melted at 100-180 C. thereby obtaining antimicrobial and antiviral surfaces. The said obtained surfaces were subjected to antimicrobial activity tests.

Embodiment 3

[0041] For 100 g antimicrobial and antiviral polyethylene (PE) composite material; 10 g zinc pyrithione, sodium borate or disodium octaborate tetrahydrate was added from the side powder feeder when 90 g PE granules were passing through the twin screw extruder at 170 C. and thus PE composite granules were obtained. Then, cold press was applied to PE composites, which were melted at 140-180 C., thereby obtaining antimicrobial and antiviral surfaces. The said obtained surfaces were subjected to antimicrobial activity tests.

Embodiment 4

[0042] For 100 g antimicrobial and antiviral polyethylene (PE) composite material; 10 g disodium octaborate tetrahydrate, 5 g zinc pyrithione and 0.2 g triclosan were added from the side powder feeder when 84.8 g PE granules were passing through the twin screw extruder at 170 C. and thus PE composite granules were obtained. Then, cold press was applied to PE composites, which were melted at 140-180 C., thereby obtaining antimicrobial and antiviral surfaces. The said obtained surfaces were subjected to antimicrobial activity tests.

Embodiment 5

[0043] For 100 g antimicrobial and antiviral polyurethane (PU) composite material; 3 g sodium borate and 0.26 g zinc pyrithione were added from the side powder feeder when 96.74 g PU granules were passing through the twin screw extruder at 170 C. and thus PU composite granules were obtained. Then, cold press was applied to PU composites which were melted at 170-220 C. thereby obtaining antimicrobial and antiviral surfaces. The said obtained surfaces were subjected to antimicrobial activity tests. [0044] In application of the invention; preferably PVC, PE, PP and PU polymers were selected; additionally Polyamide (PA), Polystyrene (PS), Polyethylene terephthalate (PET), Polycarbonate (PC), Polymethylmethacrylate (PMMA), Polydimethylsiloxane (PDMS), Polyoxymethylene (POM), Polytetrafloroethylene (PTFE), Polyether ketone (PEEK), Acrylonitrile Butadiene Styrene (ABS), Thermoplastic Elastomer (TPE), Styrene Acrylonitrile (SAN), Polylactide (PLA) polymers can also be used. [0045] Zinc borate, sodium borate, sodium perborate tetrahydrate, borax pentahydrate and disodium octaborate tetrahydrate were preferred among the boron compounds each at ratios of (1-20%). [0046] Antimicrobial and antiviral polymer composites can be obtained by mixing zinc pyrithione (1-20%) and triclosan (0.001-0.2%) at different combinations.

[0047] Antimicrobial activity tests of sections of the developed polymer composite surfaces prepared at sizes of 55 cm and 11 cm were performed via the below mentioned methods.

Antimicrobial Activity Tests of the Prepared Polymer Composite Surfaces;

[0048] Antimicrobial activity tests for antimicrobial and antiviral composite surfaces were performed simultaneously using two different methods.

[0049] In the first test method; isolates from the bacteria Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa; the yeasts Candida albicans and Candida glabrata and the fungi Aspergillus niger, Botrytis cinerea, Fusarium oxysporum, Penicillium vinaceum, Penicillium expansum were inoculated on petri dishes containing suitable media (NA, SDA and PDA respectively). Polymer surfaces prepared at sizes of 11 cm were placed on the inoculated petri dishes. The inoculated petri dishes were incubated for 24 hours for bacteria and 48 hours for yeasts at 361 C. and 72 hours for fungi at 251 C. Antimicrobial activities of the polymer composite surfaces were assessed by the inhibition zone (area where microorganisms do not grow) formed around them.

[0050] In the second method, 1 ml medium was poured on polymer composite surfaces of 55 cm placed on empty petri dishes. The media placed on the surfaces were contaminated by 100 l of the solutions (containing 10.sup.8 cfu/ml bacteria, 10.sup.6 cfu/ml yeast and 10.sup.3 spore/ml fungi) prepared from the fresh media within the buffer solution, and sterilized plastic films of 44 cm were placed thereon such that the media was prevented from overflowing. The contaminated polymer surfaces were incubated for 24 hours for bacteria and 48 hours for yeasts at 361 C. and 72 hours for fungi at 251 C. The tested polymer surfaces were washed with 10 ml PBS solution and upon performing regressive isolation via serial dilution method it was determined whether there was microbial growth thereon.

[0051] Experimental studies were carried out with certain fungus, yeast and bacteria species. Among these microorganisms, the bacteria were Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa, MRSA and VRE.

[0052] The yeasts used in the experimental studies were Candida albicans and Candida glabrata and the fungi used in the same were Fusarium oxysporum, Botrytis cinerea and Aspergillus niger.

Antiviral Tests

Antiviral Activity Tests of Chlorhexidine Gluconate and Zinc Pyrithione;

[0053] In order to produce Human adenovirus type 5 Adenoid 75 strain and poliovirus type 1 Chat strain virus and to carry out the experiment, a complete layer of HEp-2 cells (ATCC CCL-23), which are human monolayer tumor cells, were used. For determining virus titration, reference Human adenovirus type 5 Adenoid 75 strain and poliovirus type 1 Chat strain were inoculated by making serial dilutions to HEp-2 cells, and by taking as basis the virus dilution that produces a cytopathic effect visible in invert microscope, virus titration was computed by using Spearman-Karber method. In order to determine Sub-Cytotoxic concentration of Chlorhexidine gluconate and Zinc pyrithione, Chlorhexidine gluconate and zinc pyrithione were 10-fold serially diluted with Eagle's minimum essential medium (MEM) and their non-toxic concentrations in the cell medium were determined and these concentrations were used in the experiments. For the controls, MEM inoculated HEp-2 cells, full layer HEp-2 cells wherein Chlorhexidine gluconate and zinc pyrithione was not added, 10-fold diluted reference virus titration control, formaldehyde control and controls containing toxic concentrations of Chlorhexidine gluconate and zinc pyrithione were used as negative control instead of the virus.

Preparation of Cell Culture Medium and the Chemicals

[0054] MEM medium: 10% serum (FBS) containing enzymes, hormones and growth factors for the cells to be able to cling to the surfaces and proliferate; and 40 IU/ml penicillin, 0.04 mg/ml streptomycin, 0.5 mg/ml glutamine to prevent fungi and bacteria contamination; and 1% Sodium Bicarbonate as a buffer solution were added therein.

FBS: Inactivated and mycoplasma-free
Sodium bicarbonate: Sterile 7.5% solution
Medium Used in Virus Inoculation: The medium included 1% antibiotic (Penicillin, Streptomycine, Amphotericin B) in order to prevent fungi and bacteria contamination, and 1% Sodium bicarbonate as a buffer solution. FBS serum was not added to this medium.

Preparation of Clean and Contaminated Media:

[0055] Clean medium; 0.3 gr Bovine Serum Albumin Fraction V was dissolved in 100 ml sterile water. The solution that was obtained was sterilized by being passed through a filter with mesh size 0.22 M.

[0056] Contaminated medium; Sheep Erythrocyte and BSA were used for the contaminated medium. 3 g BSA was dissolved in 100 ml sterile water and filtered. 3 ml sheep erythrocyte was completed to 97 ml BSA.

[0057] Erythrocyte; 8 ml fresh sheep blood was rotated at 800 G for 10 minutes and then its supernatant was removed. Upon adding 8 ml phosphate buffer salt (PBS) thereon, pipetting was performed and it was again rotated at 800 G for 10 minutes. This procedure was repeated three times.

Analysis:

[0058] Firstly, liquid Chlorhexidine gluconate and zinc pyrithione was solid serially diluted with the cell culture medium (MEM) and its non-toxic concentration in cell culture was calculated. 8 ml of the Chlorhexidine gluconate and zinc pyrithione that was to be tested was mixed with 2 ml hard water. The obtained solution was serially diluted (dilution step 1:10) with MEM. It was inoculated in 96-well monolayered cells. The microscopic changes that occurred were recorded. Concentrations that showed cytopathic effect (CPE) were determined. Chlorhexidine gluconate, zinc pyrithione and formaldehyde CPE values were compared. After determining non-toxic concentration of chlorhexidine gluconate and zinc pyrithione on the cells, the effects of chlorhexidine gluconate and zinc pyrithione on virus titration as a result of 5-60 minutes application periods in clean and contaminated media were separately studied. For the controls, MEM inoculated HEp-2 cells, full layer HEp-2 cells wherein Chlorhexidine gluconate and zinc pyrithione was not added, 10-fold diluted reference virus titration control, formaldehyde control and controls containing toxic concentrations of Chlorhexidine gluconate and zinc pyrithione were used as negative control instead of the virus.

[0059] Taking as basis the virus dilutions wherein cytopathic effect that is visible in invert microscope is formed, virus titration was calculated as TCID.sub.50 value by using Spearman-Karber method. According to TS EN 14476 (MARCH 2007) standard, disinfectants should reduce virus titration by 4 or more logs for their antiviral activities.

Experimental Results

Antimicrobial Test Results:

[0060] Antimicrobial activity test results of the tested boron compounds are summarized in Table 1. All tests were repeated at least twice.

TABLE-US-00001 TABLE 1 Antimicrobial activity of Zinc borate (ZB), Sodium Borate (SB), Sodium perborate tetrahydrate (SPT), Borax pentahydrate (BP) and Disodium octaborate tetrahydrate (DOT) on the tested microorganisms Boron compounds Mikroorganisms ZB SB SPT BP DOT BAKTERIA Vancomycin-resistant + + + + + Enterococcus (VRE) Methicillin-resistant Staphylococcus + + + + + aureus (MRSA) Escherichia coli + + + + + Staphylococcus aureus + + + + + Pseudomonas aeruginosa + + + + + YEASTS Candida albicans + + + + + Candida glabrata + + + + + FUNGI Aspergillus spp. + + + + + Fusarium oxysporum + + + + + Botrytis cinerea + + + + + Penicillium spp. + + + + +

[0061] Antimicrobial activities of the prepared products were tested by using bacteria (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, MRSA and VRE), yeast (Candida albicans and Candida glabrata) and fungus (Fusarium oxysporum, Botrytis cinerea, Aspergillus niger, Penicillium vinaceum, Penicillium expansum Aspergillus niger, Botrytis cinerea, Fusarium oxysporu and Penicillium spp.) isolates. According to the obtained results; it was observed that polymer surfaces containing boron compounds, zinc pyrithione, triclosan and chlorhexidine gluconate had antimicrobial activity on all of the tested microorganisms. Developed antimicrobial activity test results are summarized in Table-2. Example images related to the antimicrobial activity test results are given in FIG. 1-4.

TABLE-US-00002 TABLE 2 Antimicrobial activity of the polymers containing Zinc borate (ZB), Sodium Borate (SB), Disodium octaborate tetrahydrate (DOT), Triclosan (T), Chlorhexidine gluconate (CH) and combinations thereof on the tested microorganisms POLYMERS PVC PE PU PP Combinations Microorganisms 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 NC BACTERIA Escherichia coli +.sup.a + + + + + + + + + + + + + + + .sup.b Staphylococcus aureus + + + + + + + + + + + + + + + + Pseudomonas aeruginosa + + + + + + + + + + + + + + + + MRSA + + + + + + + + + + + + + + + + VRE + + + + + + + + + + + + + + + + YEASTS Candida albicans + + + + + + + + + + + + + + + + Candida glabrata + + + + + + + + + + + + + + + + FUNGI Aspergillus niger + + + + + + + + + + + + + + + + Botrytis cinerea + + + + + + + + + + + + + + + + Fusarium oxysporum + + + + + + + + + + + + + + + + Penicillium spp. + + + + + + + + + + + + + + + + .sup.a+ sign indicates that the boron compounds had antimicrobial activity. .sup.b sign indicates that there is no antimicrobial activity. 1: PVC containing 2.5% ZP, 10% SB and 0.2% T 2: PVC containing 3% ZP and 3% DOT 3: PVC containing 3% ZP and 0.2% T 4: PVC containing 15% SB and 2% CH 5: PE containing 2 5% ZP, 10% SB and 0.2% T 6: PE containing 3% ZP and 3% DOT 7: PE containing 3% ZP and 0.2% T 8: PE containing 15% SB and 2% CH 9: PU containing 2.5% ZP, 10% SB and 0.2% T 10: PU containing 3% ZP and 3% DOT 11. PU containing 3% ZP and 0.2% T 12: PU containing 15% SB and 2% CH 13: PP containing 2 5% ZP, 10% SB and 0.2% T 14: PP containing 3% ZP and 3% DOT 15: PP containing 3% ZP and 0.2% T 16: PP containing 15% NaB and 2% CH NC: Negative control; PVC, PE, PU, PP not containing any additives

Antiviral Tests:

[0062] It was observed in the calculations made as a result of the test that chlorhexidine gluconate caused at least 4 log reduction in virus titer at all experiment conditions (Table 53 and Table 4) as a result of application at a ratio of 1/1, at room temperature (20 C.), in clean and contaminated media and with 1 and 60 minute application periods. According to Antimicrobial Division US EPA standards, disinfectants should reduce virus titer by 4 or more logs for their virucidal activities.

TABLE-US-00003 TABLE 3 Antiviral activity of chlorhexidine gluconate in Hep-2 cell culture against Human adenovirus type 5 virus Adenoid 75 strain Chlorhexidine Gluconate Reference virus 1 minute 60 minutes Virus titer* 5.5 Clean Contamin. Clean Contamin. medium medium medium medium Virus titer with disinfectant** 1.5 1.5 1.5 1.5 Reduction ratio in virus 4.0 4.0 4.0 4.0 titer*** *Logarithmic TCID.sub.50 value of the virus in ml. **Logarithmic TCID.sub.50 value of the virus treated with the disinfectant at different periods and media. ***Logarithmic TCID50 ratio between the virus titer and the virus titer with disinfectant

TABLE-US-00004 TABLE 4 Antiviral activity of chlorhexidine gluconate in HEp-2 cell culture against poliovirus type 1 virus Chat strain Chlorhexidine Gluconate Reference virus 1 minute 60 minutes Virus titer* 6.0 Clean Contamin. Clean Contamin. medium medium medium medium Virus titer with disinfectant** 2.0 2.0 2.0 2.0 Reduction ratio in virus 4.0 4.0 4.0 4.0 titer*** *Logarithmic TCID.sub.50 value of the virus in ml. **Logarithmic TCID.sub.50 value of the virus treated with the disinfectant at different periods and media. ***Logarithmic TCID.sub.50 ratio between the virus titer and the virus titer with disinfectant

[0063] It was observed in the calculations made as a result of the test that zinc pyrithione caused at least 4 log reduction in virus titer at all experiment conditions (Table 5 and Table 6) as a result of application at a ratio of 1/1, at room temperature (20 C.), in clean and contaminated media and with 1 and 60 minute application periods. According to Antimicrobial Division US EPA standards, disinfectants should reduce virus titer by 4 or more logs for their virucidal activities.

TABLE-US-00005 TABLE 5 Antiviral activity of zinc pyrithione in HEp-2 cell culture against Human adenovirus type 5 virus Adenoid 75 strain Zinc pyrithione Reference virus 1 minute 60 minutes Virus titer* 5.0 Clean Contamin. Clean Contamin. medium medium medium medium Virus titer with disinfectant** 1.0 1.0 1.0 1.0 Reduction ratio in virus 4.0 4.0 4.0 4.0 titer*** *Logarithmic TCID.sub.50 value of the virus in ml. **Logarithmic TCID.sub.50 value of the virus treated with the disinfectant at different periods and media. ***Logarithmic TCID.sub.50 ratio between the virus titer and the virus titer with disinfectant

TABLE-US-00006 TABLE 6 Antiviral activity of zinc pyrithione in Hep-2 cell culture against poliovirus type 1 virus Chat strain Zinc pyrithione Reference virus 1 minute 60 minutes Virus titer* 5.5 Clean Contamin. Clean Contamin. medium medium medium medium Virus titer with disinfectant** 1.5 1.0 1.5 1.5 Reduction ratio in virus 4.0 4.5 4.0 4.0 titer*** *Logarithmic TCID.sub.50 value of the virus in ml. **Logarithmic TCID.sub.50 value of the virus treated with the disinfectant at different periods and media. ***Logarithmic TCID50 ratio between the virus titer and the virus titer with disinfectant

[0064] As a conclusion; these experiment results show that chlorhexidine gluconate and zinc pyrithione is 99.9% active against Human adenovirus type 5 virus and 99.9% active against poliovirus type 1 virus when used directly without being diluted at room temperature (20 C.) within 1 and 60 minute application periods.

[0065] The composite polymers of the present invention are used in the medical industry which is required to be antimicrobial. The said composites do not cause any toxic or irritant effect on human body.

[0066] The present invention can be used in all kinds of polymeric surfaces. Antimicrobial and antiviral surfaces will be developed in a very broad spectrum to be used in textile, electronic goods, automotive industry, medical sector, construction materials, agriculture, biomedical science, packaging, hygiene, food, industrial design, sports goods, energy industry, defense industry, and in all sectors wherein antimicrobial and antiviral activities are desired and biodegradation is desired to be controlled.