PROCESS FOR PRODUCING WATER-SOLUBLE HYALURONIC ACID MODIFICATION

摘要

A water-soluble HA modification practical as a drug support; and a process for producing the modification. The water-soluble hyaluronic acid modification is produced by incorporating substituents into carboxy groups of the glucuronic acid moieties in either hyaluronic acid or a derivative thereof through an amide bond with the aid of a BOP condensation agent in an aprotic polar solvent, the amount of the substituents being at least 5 mol%. This modification can reside in the blood in a prolonged period on a practical level. Crosslinking the hyaluronic acid modification gives a hyaluronic acid gel. This gel can release a drug over a far longer period than known gels even when the proportion of crosslinkable functional groups introduced is the same.