Patent ID: 7910135
Filing Date: 2011-03-22
Classification: A61L,A61P,Y10S

Abstract:
1. A dry powder of polymeric nanoparticles that will form a shape-retentive aggregate upon exposure to a physiological medium or other medium of similar ionic strength, prepared by a method comprising: (a) polymerizing an effective amount of a monomer or two or more monomers, selected from the group consisting of a 2-alkenoic acid, a hydroxy (2C-4C) alkyl 2-alkenoate, a dihydroxy (2C-4C) alkyl 2-alkenoate, a hydroxy (2C-4C) alkoxy (2C-4C) alkyl 2-alkenoate, a (1C-4C) alkoxy (2C-4C) alkoxy (2C-4C) alkyl 2-alkenoate and a vicinyl epoxy (1C-4C) alkyl 2-alkenoate, a polar liquid or a mixture of two or more miscible liquids, at least one of which is polar, and from about 0.01 to about 0.1 weight percent of surfactant to produce a suspension of a plurality of polymeric nanoparticles wherein the polymeric nanoparticles have an average diameter of from about 20 to about 300 nm; and (b) removing the liquid(s) from the suspension in such a manner as to prevent aggregation and such that the amount of liquid(s) remaining in the dry powder is less than 10% by weight wherein the percentage is based on the total weight of the dry powder.