Methods to produce polymer nanoparticles and formulations of active ingredients

Abstract

The present invention provides a composition including a polymer nanoparticle and at least one agricultural active compound incorporated with the nanoparticle, wherein the nanoparticle are less than 100 nm in diameter, and the polymer includes a polyelectrolyte.

What is claimed is: 
     
         1 . A method comprising steps of
 (a) dissolving a polyelectrolyte into an first solvent under solution conditions that render it charged,   (b) adding a species that is oppositely charged under these conditions to cause the polyelectrolyte to collapse upon the oppositely charged species,   (c) crosslinking the collapsed polyelectrolyte,   (d) removing the oppositely charged species from the solution; and   (e) associating an active ingredient with the collapsed and cross-linked polyelectrolyte.   
     
     
         2 . The method of  claim 1 , wherein the active ingredient is an organic, neutral agricultural active compound. 
     
     
         3 . The method of  claim 1 , wherein the first solvent comprises water. 
     
     
         4 . The method of  claim 2 , wherein the active ingredient is non-ionic. 
     
     
         5 . The method of  claim 2 , wherein the polyelectrolyte is water-soluble and has a molecular weight of at least about 100,000 Dalton. 
     
     
         6 . The method of  claim 2 , wherein the active ingredient is selected from the group consisting of an acaracide, an insecticide, a fungicide, a bactericide, a herbicide, an antibiotic, an antimicrobial, a nemacide, a rodenticide, an entomopathogen, a pheromone, a chemosterilant, a virus, an attractant, a plant growth regulator, an insect growth regulator, a repellent, a plant nutrient, a phagostimulant, a germicide, and combinations thereof. 
     
     
         7 . The method of  claim 6 , wherein the active ingredient is selected from the group consisting of strobilurins, pyrethroids, triazoles and sulfonamides. 
     
     
         8 . The method of  claim 1 , wherein the removing step comprises dialysis or diafiltration. 
     
     
         9 . The method of  claim 1 , wherein the removing step comprises dissolving the oppositely charged species. 
     
     
         10 . The method of  claim 1 , further comprising a step of drying the collapsed and cross-linked polyelectrolyte before the associating step. 
     
     
         11 . The method of  claim 1 , wherein the collapsed and cross-linked polyelectrolyte is less than 100 nm in size. 
     
     
         12 . The method of  claim 1 , wherein the collapsed and cross-linked polyelectrolyte is less than 20 nm in size. 
     
     
         13 . The method of  claim 1 , wherein the collapsed and cross-linked polyelectrolyte comprises multiple polyelectrolyte molecules. 
     
     
         14 . The method of  claim 1 , wherein the polyelectrolyte is a copolymer. 
     
     
         15 . The method of  claim 1 , wherein the polyelectrolyte is a random copolymer. 
     
     
         16 . The method of  claim 10 , wherein the associating step comprises:
 (a) dissolving the dried, collapsed and cross-linked polyelectrolyte and active ingredient in a solvent; and   (b) removing at least a portion of the solvent.   
     
     
         17 . The method of  claim 16 , wherein the solvent comprises an organic solvent. 
     
     
         18 . A method comprising steps of:
 (a) dissolving a polyelectrolyte into a first solvent under solution conditions that render it charged,   (b) adding a species that is oppositely charged under these conditions to cause the polyelectrolyte to collapse upon the oppositely charged species,   (c) crosslinking the collapsed polyelectrolyte,   (d) removing the oppositely charged species from the solution,   (e) drying the resulting solution to produce a composition,   (f) dissolving the composition and an active ingredient in a second solvent; and   (g) removing at least a portion of the second solvent.   
     
     
         19 . The method of  claim 18 , wherein the second solvent comprises an organic solvent. 
     
     
         20 . The method of  claim 18 , wherein the active ingredient is an organic, neutral agricultural active compound. 
     
     
         21 . The method of  claim 20 , wherein the active ingredient is non-ionic. 
     
     
         22 . The method of  claim 18 , wherein the polyelectrolyte is water-soluble and has a molecular weight of at least about 100,000 Dalton. 
     
     
         23 . The method of  claim 18 , wherein the active ingredient is selected from the group consisting of an acaracide, an insecticide, a fungicide, a bactericide, a herbicide, an antibiotic, an antimicrobial, a nemacide, a rodenticide, an entomopathogen, a pheromone, a chemosterilant, a virus, an attractant, a plant growth regulator, an insect growth regulator, a repellent, a plant nutrient, a phagostimulant, a germicide, and combinations thereof. 
     
     
         24 . The method of  claim 23 , wherein the active ingredient is selected from the group consisting of strobilurins, pyrethroids, triazoles and sulfonamides. 
     
     
         25 . The method of  claim 18 , wherein the collapsed and cross-linked polyelectrolyte is less than 100 nm in size. 
     
     
         26 . The method of  claim 18 , wherein the collapsed and cross-linked polyelectrolyte is less than 20 nm in size. 
     
     
         27 . The method of  claim 18 , wherein the collapsed and cross-linked polyelectrolyte comprises multiple polyelectrolyte molecules. 
     
     
         28 . The method of  claim 18 , wherein the polyelectrolyte is a copolymer. 
     
     
         29 . The method of  claim 18 , wherein the polyelectrolyte is a random copolymer. 
     
     
         30 . The method of  claim 18 , further comprising a step of drying the remaining solution after removal of the first solvent.