Patent ID: 7759088

Claim:
A method for the production of a biodegradable, water absorbable γ-polyglutamic acid (γ-PGA) hydrogel comprising directly cross-linking (A) a γ-polyglutamate and optionally a polysaccharide containing a carboxylic acid group, and/or carboxylate group, an amino acid, or a mixture thereof; or (B) a microbial culture broth containing a γ-polyglutamate and optionally a polysaccharide containing a carboxylic acid group and/or carboxylate group, an amino acid, or a mixture thereof; and a cross-linker comprising a polyglycidyl ether having three or more functional groups, wherein the functional groups thereon can react with a carboxylic group (—COOH), carboxylate group (—COO − ), aldehyde group (—CHO), hydroxyl (—OH), carbonyl group (—CO), sulfone group (—SO 2 ), amino group (—NH 2 ) or a nitro group (NO 2 ) or a mixture thereof, and wherein said polyglycidyl ether is glycerol triglycidyl ether, di- or polyglycerol polyglycidyl ether and polyoxyethylene sorbitol polyglycidyl ether, or a mixture thereof.