US Patent 11198765 Hydrolysis of ester bonds in amide crosslinked glycosaminoglycans

A method of preparing a hydrogel product comprising crosslinked glycosaminoglycan molecules, said method including: i) providing a glycosaminoglycan crosslinked by amide bonds, wherein the crosslinked glycosaminoglycans include ester crosslinks formed as byproducts during the amide crosslinking; and ii) subjecting the crosslinked glycosaminoglycans to alkaline treatment to hydrolyze ester crosslinks formed as byproducts during the amide crosslinking.