Porous nanoparticles produced by solvent-free emulsification

Abstract

Disclosed herein are porous nanoparticles having a particle size of from about 50 nm to about 2 μm and a pore diameter of from about 20 nm to about 400 nm. The porous nanoparticles include a resin composition comprising at least one polyester resin in the absence of an organic solvent, and a surfactant.

What is claimed is: 
     
         1 . Porous nanoparticles comprising:
 a resin composition comprising at least one polyester resin in the absence of an organic solvent, and   a surfactant;   
       wherein the porous nanoparticles have a particle size of from about 50 nm to about 2 μm, a pore diameter of from about 20 nm to about 400 nm, and a surface porosity of from about 10% to 60% of the surface of the porous nanoparticles. 
     
     
         2 . The porous nanoparticles according to  claim 1 , wherein the porous nanoparticles have cell walls with a cell wall thickness of from about 5 nm to about 100 nm. 
     
     
         3 . The porous nanoparticles according to  claim 1 , wherein the at least one polyester resin is selected from the group consisting of amorphous resins, crystalline resins, and combinations thereof. 
     
     
         4 . The porous nanoparticles according to  claim 3 , wherein the at least one polyester resin comprises an amorphous resin. 
     
     
         5 . The porous nanoparticles according to  claim 1 , wherein the porous nanoparticles comprise pores loaded with at least one active compound selected from the group consisting of a cosmetic compound, a chemical compound and a pharmaceutical compound. 
     
     
         6 . The porous nanoparticles according to  claim 1 , wherein the ratio by weight of the at least one active compound to the weight of the porous nanoparticles is from about 1:1000 to about 10:1. 
     
     
         7 . The porous nanoparticles according to  claim 1 , wherein the at least one active compound is present in the porous nanoparticles in an amount of from about 1 to 43% by weight relative to the total weight of the porous nanoparticles once loaded. 
     
     
         8 . The porous nanoparticles according to  claim 1 , wherein the surfactant is present in an amount of from about 0.01% to about 20% by weight of the resin composition. 
     
     
         9 . Porous nanoparticles comprising:
 a resin composition comprising at least one polyester resin in the absence of an organic solvent, and   a surfactant;   
       wherein the porous nanoparticles have a particle size of from about 75 nm to about 1 μm, a pore diameter of from about 25 nm to about 180 nm, and a surface porosity of from about 10% to 60% of the surface of the porous nanoparticles. 
     
     
         10 . The porous nanoparticles according to  claim 9 , wherein the porous nanoparticles have cell walls with a cell wall thickness of from about 10 nm to about 50 nm. 
     
     
         11 . Porous nanoparticles comprising:
 a resin composition comprising at least one polyester resin in the absence of an organic solvent, and   a surfactant;   
       wherein the porous nanoparticles have a particle size of from about 50 nm to about 2 μm and a pore diameter of from about 20 nm to about 400 nm, and a surface porosity of from about 10% to 60% of the surface of the porous nanoparticles; 
       wherein 
       the porous nanoparticles are produced by a process comprising:
 adding a first aqueous solution comprising a surfactant to the resin composition comprising at least one resin to form a water-in-oil emulsion; 
 adding a second aqueous solution comprising deionized water to the water-in-oil emulsion prior to phase inversion to form a water-in-oil-in-water double emulsion comprising porous nanoparticles; and 
 recovering porous nanoparticles from the double emulsion. 
 
     
     
         12 . The porous nanoparticles according to  claim 11 , wherein the resin composition further comprises a neutralizing agent. 
     
     
         13 . The porous nanoparticles according to  claim 12 , wherein the neutralizing agent is sodium hydroxide. 
     
     
         14 . The porous nanoparticles according to  claim 12 , wherein the neutralizing agent is present in an amount of from about 0.001% by weight to about 50% by weight of the resin composition. 
     
     
         15 . The porous nanoparticles according to  claim 11 , further comprising adding deionized water after formation of the double emulsion. 
     
     
         16 . The porous nanoparticles according to  claim 11 , wherein the first aqueous solution comprising a surfactant further comprises at least one active compound selected from the group consisting of a cosmetic compound, a chemical compound and a pharmaceutical compound. 
     
     
         17 . The porous nanoparticles according to  claim 11 , wherein the first aqueous solution comprising a surfactant is fed at a rate such that the surfactant is at a concentration of from about 2% by weight to about 15% by weight of the resin. 
     
     
         18 . The porous nanoparticles according to  claim 11 , wherein the second aqueous solution further comprises a surfactant. 
     
     
         19 . The porous nanoparticles according to  claim 11 , wherein the porous nanoparticles have cell walls with a cell wall thickness of from about 5 nm to about 100 nm. 
     
     
         20 . The porous nanoparticles according to  claim 11 , wherein the at least one polyester resin is selected from the group consisting of amorphous resins, crystalline resins, and combinations thereof.