Patent ID: 7060296

Claim:
A biodegradable hydrogel comprising a network of polymer chains, wherein said network contains polymer backbones which are interconnected to one another through spacers formed by crosslinked units, wherein the spacers contain, between said polymer backbone and the crosslinked unit, one or more bonds which are hydrolysable under physiological conditions, wherein at least one of the bonds which are hydrolysable under physiological conditions comprises a carbonate ester bond; wherein said crosslinked unit is comprised of a polymer of a) (poly)glycolic acid and/or (poly)lactic acid, and b) at least one monomer containing an acrylate, methacrylate and/or hydroxyalkyl methacrylate groups, wherein at least one of the groups is connected to the polymer backbone; and wherein said polymer backbones are selected from the group consisting of dextran, derivitized dextran, starch, starch derivatives, hydroxyethyl cellulose, hydroxypropyl cellulose, polyvinylpyrrolidone, polyvinylalcohol, polyacrylate, polymethacrylate, and polyethylene glycol.