METAL-POLYMER FUNGICIDAL- BIOCIDAL PROTECTION SYSTEMS. Orley Pinchuk. Thursday, March 23 Wood Protection 2006 New Orleans, Louisiana, USA

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1 METAL-POLYMER FUNGICIDAL- BIOCIDAL PROTECTION SYSTEMS Orley Pinchuk Thursday, March 23 Wood Protection 2006 New Orleans, Louisiana, USA

2 Outline 1. Introduction to Fungi 2. Metals antifungal 3. Polymers importance 4. Our Product 5. Testing Methods 6. Verification Testing 7. Summery / Conclusion

3 Introduction Fungi Their own Kingdom Eukaryotic Plant-like like (no chlorophyll) Growth requirements = organic carbon sources (cellulose) + water + warm temperature

4 FUNGI YEAST MOULD Multiple small round forms Actively dividing and growing Budding (fission) Colonies = moist and gooey Filamentous hyphae form mycelium Grow by elongation of mycelium tips (condida or spores)

5 Many colors, including: Introduction WOOD FUNGI White Rot Fungi Brown Rot Fungi Basidiomycetes Utilize their lignin and cellulose degrading enzymes to degrade wood efficiently Large impact on logging and lumber industries

6 Common Practices pre- ; in-place ; post- treatment systems Borate Treatments Wood Modification IPBC QUAT Azoles Copper treatments Bull-dozing (& rebuilding?) Pros and cons to each which one is preferred? Driving force for new technology and practices

7 Our Technology Oligodynamic metal ion in a hydrophilic polymer binder or carrier What we are currently using: metal ion silver hydrophilic polymer sulfonated polystyrene Applied by spraying, fogging, dipping, soaking, incorporating it into the matrix (composites) Non-toxic to humans, inexpensive, easy to apply

8 Metals: How they work

9 Why Metals? Most heavy metals, such as silver, copper, zinc and gold exhibit extraordinary antimicrobial affects. Silver, however has been proven to have the highest antimicrobial effect in regards to bacterial, fungal and viral cells, and the lowest effect in regards to human and animal cells

10 Why Silver? Historically: Macedonian culture 1 st used silver salts to cover wounds Long Phoenician voyages, water, wine and vinegar were stored in silver vats to ensure the purity and safety of their drinking fluids The pioneers moving west towards America then dropped silver coins in their barrels of drinking water Babies fed with silver spoons were recorded to have better health than the rest who were fed with other metal-comprised spoons

11 Metallic Antimicrobials Release metal ions into the microbe react with protein and other anions in the microbe render the protein insoluble and thereby inactive Inactive protein: perturbs cellular function disrupts membranes prevents the normal activity and replication of DNA killing the microorganism

12 Example of how silver ions affect BACTERIAL cells Left regular dispersion of the DNA in the cell Right DNA agglomerated in the center of the cell Untreated Treated

13 Polymers: How they work

14 Why Polymers? Polymer: A chemical compound or mixture consisting essentially of repeating structural units - Stable carrier when equipped with appropriately selected R-groups - Hydrophilic or hydrophobic - custom

15 Why Sulfonated Sulfonated Polystyrene? provides negative charges to ionically bind the selected positive charged ionic metals very stable longevity, will not rot slow release of antimicrobial agents hydrophilic aqueous solution

16 Testing Methods Filter paper test: Treat 2 sq. mm filter paper in triplicate, dry Place on previously inoculated agar plate, incubate Once controls visible, re-streak surface onto fresh agar, incubate Yes/no ideal mixture, synergistic/antagonistic

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18 Testing Methods Filter paper test: Treat 2 sq. mm filter paper in triplicate, dry Place on previously inoculated agar plate, incubate Once controls visible, re-streak surface onto fresh agar, incubate Yes/no ideal mixture, synergistic/antagonistic Adjust concentration no leaching (ZOI) + no growth upon re- streaking NOTE: Ensure no leaching into surrounding environment,, (water supply and food chain) ZOI is not desired: want to be effective on the surface ONLY Will diffuse throughout the substrate to a certain degree

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21 Lab Testing Methods DOW 923 test Shake-Flask test ASTM D testing concentrations as well as on individual fungal species Price, D.L. and Ahearn, D.G. (1999) Sanitation of wallboard colonized with Stachybotrys chartarum. Current Microbiology 39: Individual humidity chambers for each dilution Variety of fungi tested in inoculate

22 One of many Field Testings Mold-infested ceiling in Venis,, FL 9 sq. ft treated (cleaned then treated) Regular airflow between treated and untreated areas 75% humidity Moisture content on treated half 30% 7 months later swabbed comparable sized areas on both treated and untreated surfaces Placed directly into sterile solution and sent to 3 rd party lab for analysis

23 UNTREATED

24 TREATED

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27 Verification Methods Product: Particle counter ICP FTIR Fungi: Re-streaking methods (viable / non-viable) AFM (changes in morphology) FTIR (chemical changes) FPA-FTIR FTIR (where the chemical changes are)

28 Summary 1) Fungi 2) Silver Controlled by proper cleaning and sterilization Prevented by regulating moisture / ventilation / preservation treatment Effective preservative Not used in harmful concentrations Used in desired usage range not to leech out still full destruction of fungal population 3) Sulfonated polystyrene R-groups give ions for silver ion adsorption Stable, hydrophilic

29 Conclusions Currently Used Embodiment of silver and sulfonated polystyrene very effective cost / kill / safety Continuing research constantly carried out On-going testing with long-term testing methods All in all, it gets the job done!

30 The End