Green synthesis of nanometals using plant extracts and use thereof

Abstract

The present invention relates to methods of making and using and compositions of metal nanoparticles formed by green chemistry synthetic techniques. For example, the present invention relates to metal nanoparticles formed with solutions of plant extracts and use of these metal nanoparticles in removing contaminants from soil and groundwater and other contaminated sites. In some embodiments, the invention comprises methods of making and using compositions of metal nanoparticles formed using green chemistry techniques.

1 . A method for making one or more metal nanoparticles, comprising:
 providing a solution comprising a first metal ion;   providing a plant extract that comprises a reducing agent, a polyphenol, caffeine, and/or a natural solvent or surfactant; and   combining the first metal ion solution and the plant extract to produce metal nanoparticles; wherein the metal is selected from the group consisting of iron, manganese, palladium, copper, indium, and combinations.   
     
     
         2 - 9 . (canceled) 
     
     
         10 . The method of  claim 1 , wherein the providing of the solution comprising the first metal ion, the providing of the plant extract, and the combining of the first metal ion solution and the plant extract to produce metal nanoparticles are conducted at about room temperature. 
     
     
         11 . The method of  claim 1 , wherein the reducing agent, polyphenol, caffeine, and/or a natural solvent or surfactant is selected from the group consisting of tea extract, green tea extract, coffee extract, lemon balm extract, polyphenolic flavonoid, flavonoid, flavonol, flavone, flavanone, isoflavone, flavans, flavanol, anthocyanins, proanthocyanins, carotenoids, catechins, quercetin, rutin, and combinations. 
     
     
         12 . (canceled) 
     
     
         13 . The method of  claim 1 , wherein the plant extract is obtained from a waste product selected from the group consisting of fruit juice pulp, fruit juice manufacturing wastewater, fruit juice manufacturing waste, food processing waste, food processing byproduct, wine manufacturing waste, beer manufacturing waste, and forest product processing waste. 
     
     
         14 . The method of  claim 1 , wherein the natural solvent or surfactant is selected from the group consisting of VeruSOL™-3, Citrus Burst 1 (CB-1), Citrus Burst 2 (CB-2), Citrus Burst 3 (CB-3), EZ-Mulse, and combinations. 
     
     
         15 . The method of  claim 1 , further comprising:
 providing a second solution of a metal ion, and   combining the first metal ion solution, the second metal ion solution and the plant extract to produce metal nanoparticles comprising first and second metals.   
     
     
         16 - 21 . (canceled) 
     
     
         22 . The method of  claim 1 , wherein the metal ion is an iron ion. 
     
     
         23 . The method of  claim 1 , wherein the solution comprises ferric chloride (FeCl 3 ), ferrous sulfate (FeSO 4 ), ferric nitrate (Fe(NO 3 ) 3 ), Fe(III)-EDTA, Fe(III)-citric acid, Fe(III)-EDDS, Fe(II)-EDTA, Fe(II)-citric acid, and/or Fe(II)-EDDS. 
     
     
         24 - 41 . (canceled) 
     
     
         42 . The method of  claim 1 , wherein the first metal ion is present in a medium to be treated. 
     
     
         43 . The method of  claim 1 , wherein the first metal ion is provided in a medium to be treated by adding a chelating agent to a soil and/or water sample to be treated. 
     
     
         44 . (canceled) 
     
     
         45 . A composition comprising zero valent metal nanoparticles and a plant extract or component of the plant extract that comprises a reducing agent, a polyphenol, caffeine, and/or a natural solvent or surfactant wherein the metal nanoparticles comprise one or more of iron, manganese, palladium, copper, indium, and combinations. 
     
     
         46 . The composition of  claim 45 , wherein the metal nanoparticles are coated with a substance derived from the plant extract. 
     
     
         47 - 50 . (canceled) 
     
     
         51 . The composition of  claim 45 , wherein the metal nanoparticles are substantially non-aggregated. 
     
     
         52 . The composition of  claim 45 , comprising a natural solvent or surfactant. 
     
     
         53 . The composition of  claim 52 , wherein the natural solvent or surfactant is selected from the group consisting of VeruSOL™-3, Citrus Burst 1 (CB-1), Citrus Burst 2 (CB-2), Citrus Burst 3 (CB-3), EZ-Mulse and combinations. 
     
     
         54 . The composition of  claim 45 , further comprising a chelating agent. 
     
     
         55 . (canceled) 
     
     
         56 . The composition of  claim 45 , further comprising an oxidant. 
     
     
         57 . (canceled) 
     
     
         58 . The composition of  claim 45 , further comprising a carboxy methyl cellulose coating or a hydrophobic coating on the surface of the nanoparticles. 
     
     
         59 . (canceled) 
     
     
         60 . The composition of  claim 45 , wherein the metal nanoparticles comprise zero valent metal and a component of the plant extract. 
     
     
         61 . (canceled) 
     
     
         62 . The composition of  claim 45 , wherein the metal nanoparticles comprise at least two different metals. 
     
     
         63 - 88 . (canceled) 
     
     
         89 . The composition of  claim 45 , wherein the metal nanoparticles are coated with a phenolic compound of the plant extract.