Compositions and methods for antimicrobial metal nanoparticles

Abstract

Embodiments of the invention are directed to a composition having antimicrobial activity comprising particles comprising at least one inorganic copper salt; and at least one functionalizing agent in contact with the particles, the functionalizing agent stabilizing the particle in a carrier such that an antimicrobially effective amount of ions are released into the environment of a microbe. The average size of the particles ranges from about 1000 nm to about 4 nm. Preferred copper salts include copper iodide, copper bromide and copper chloride. Preferred functionalizing agents include amino acids, thiols, hydrophilic polymers emulsions of hydrophobic polymers and surfactants.

1 - 30 . (canceled) 
     
     
         31 . A method of inhibiting growth of or killing bacteria comprising the steps of contacting a bacterial environment with an effective amount of a composition comprising:
 (a) particles comprising at least one inorganic copper salt; and   (b) at least one functionalizing agent in contact with said particles, said functionalizing agent stabilizing said particles in a carrier such that an antibacterially effective amount of ions are released into the bacterial environment.   
     
     
         32 . The method of  claim 31  wherein said carrier is a liquid. 
     
     
         33 . The method of  claim 32  wherein said functionalizing agent is soluble in said liquid carrier. 
     
     
         34 . The method of  claim 32  wherein said functionalizing agent is insoluble in said liquid carrier but stabilizes said particles in said liquid carrier. 
     
     
         35 . The method of  claim 31  wherein said particles are complexed by said functionalizing agent. 
     
     
         36 . The method of  claim 32  wherein said liquid carrier is water-based. 
     
     
         37 . The method of  claim 32  wherein said liquid carrier is oil-based. 
     
     
         38 . The method of  claim 32  wherein said particles are suspended in said liquid carrier. 
     
     
         39 . The method of  claim 31  wherein said carrier is a solid. 
     
     
         40 . The method of  claim 39  wherein said solid carrier comprises a melt-blend plastic. 
     
     
         41 . The method of  claim 31  wherein said inorganic copper salt comprises a copper halide salt. 
     
     
         42 . The method of  claim 31  wherein contacting a bacterial environment comprises dispersing said composition in a monomer or polymer in an antibacterially effective amount, and then applying said monomer or polymer dispersion to a surface capable of being protected against the presence of bacteria. 
     
     
         43 . The method of  claim 31  wherein contacting a bacterial environment comprises dispersing said composition in a liquid in an antibacterially effective amount, and then contacting a surface with said dispersion. 
     
     
         44 . The method of  claim 43  wherein the liquid additionally contains a film-forming polymer or precursors which form a polymeric coating after contacting said surface. 
     
     
         45 . The method of  claim 39  wherein contacting a bacterial environment comprises dispersing said composition in a melt-blend, extrudable or injection moldable polymer. 
     
     
         46 . The method of  claim 32  wherein the step of contacting a microbial environment comprises applying a coating comprising said composition to a surface whereby a solvent present in the carrier evaporates leaving the remaining composition on said surface. 
     
     
         47 . The method of  claim 46  wherein said carrier additionally comprises one or more film-forming polymers or precursors which form a polymeric coating after applying to said surface. 
     
     
         48 . The method of  claim 45  further comprising the step of combining said dispersion with other melt-blend, extrudable or injection moldable-capable polymers, and then manufacturing an article from said composition dispersed in said melt-blend, extrudable or injection-moldable polymer. 
     
     
         49 . The method of  claim 31  wherein the composition contains at least about 12 ppm of the antibacterially-effective composition. 
     
     
         50 . The composition of  claim 41  wherein said halide is Iodide. 
     
     
         51 . The composition of  claim 31  wherein said particles have an average size range of from about 1000 nm to about 4 nm. 
     
     
         52 . The method of  claim 31  wherein said inorganic copper salt has a solubility of less than 100 mg/liter in water at room temperature. 
     
     
         53 . The method of  claim 31  wherein said inorganic copper salt has a solubility of less than 15 mg/liter in water at room temperature. 
     
     
         54 . The method of  claim 31  wherein said functionalizing agent is selected from the group consisting of amino acids, thiols, hydrophilic polymers, emulsions of hydrophobic polymers, surfactants and ligand-specific binding agents. 
     
     
         55 . The method of  claim 54  wherein said amino acid is selected from any of aspartic acid, leucine and lysine. 
     
     
         56 . The method of  claim 54  wherein said thiol is selected from the group consisting of aminothiol, thioglycerol, thioglycine, thiolactic acid, thiomalic acid, thiooctic acid and thiosilane. 
     
     
         57 . The method of  claim 54  wherein said hydrophilic polymer is selected from the group consisting of polyvinylpyrrolidone, polyethyleneglycol and copolymers and blends comprising at least one of the monomers which form the said polymers. 
     
     
         58 . The method of  claim 54  wherein said hydrophobic polymer is selected from the group consisting of polyurethanes, acrylic polymers, epoxies, silicones and fluorosilicones. 
     
     
         59 . The method of  claim 54  wherein said amphiphilic polymer is selected from the group consisting of PVP-block-polypropyleneoxide-block, polyethyleneoxide-block-polypropyleneoxide-block-polyethyleneoxide-block, and polyethyleneoxide-block-polypropylene oxide-block. 
     
     
         60 . The method of  claim 41  wherein said functionalizing agent complexes said copper halide. 
     
     
         61 . The method of  claim 31  wherein said inorganic copper salt is selected from the group consisting of copper thiocyanate and copper oxide. 
     
     
         62 . The method of  claim 31  wherein contacting a bacterial environment comprises dispersing said composition in a polymeric coating. 
     
     
         63 . The method of  claim 31  wherein contacting a bacterial environment comprises dispersing said composition in a suspension. 
     
     
         64 . A method of inhibiting growth of or killing bacteria comprising the steps of contacting a bacterial environment with an effective amount of a composition comprising:
 (a) particles comprising at least one inorganic copper salt selected from the group consisting of CuI, CuBr and CuCl and having an average size of less than about 1000 nm; and   (b) at least one functionalizing agent in contact with said particles, said functionalizing agent being present at a weight ratio of from about 100:1 to about 0.5:1.