Patent ID: 7964217
Filing Date: 2011-06-21
Classification: A61K,C08G

Abstract:
1. A crosslinked polymeric structure comprising poly(ethylene glycol) (PEG) polymers in the absence of non-PEG polymers, said PEG polymers crosslinked in the absence of photopolymerization or free-radical polymerization so as to form a solid aggregate and having at least some hydrolytically unstable linkages present in the backbone of said crosslinked PEG polymers that are hydrolyzable under hydrolysis conditions such that the crosslinked polymeric structure is hydrolytically degradable into smaller PEG fragments, said hydrolyzable linkages comprising linkages selected from the group consisting of carboxylate esters, phosphate esters, imines, hydrazones, acetals, and orthoesters, wherein the carboxylate ester is an ester according to the formula —O—(CH 2 ) r —CO 2 —, wherein r is from 1 to 10, wherein the polymeric structure is in the form of a hydrogel that swells in water.