Patent ID: 6031017
Filing Date: 2000-02-29
Classification: A61L,C08B

Abstract:
An injectable photocured crosslinked-hyaluronic acid hydrogel having a network structure containing an aqueous medium, said gel having a storage modulus (G') of from 50 to 1500 Pa, a loss modulus (G"") of from 10 to 300 Pa, and a tangent delta (G""/G') of from 0.1 to 0.8 in dynamic viscoelasticity measured by a rheometer under the following conditions,method of measurement:oscillation test method, stress controlmeasuring temperature: 37.degree. C.measuring geometry: 4 cmgap: 800 .mu.mfrequency: 10 Hz, andwhich is a hydrogel obtained by irradiation with ultraviolet rays of a photoreactive hyaluronic acid derivative in which a photoreactive crosslinking group is chemically linked to a functional group of the hyaluronic acid and crosslinking of mutual photoreactive crosslinking groups.wherein said photoreactive crosslinking group is a cinnamic acid derivative containing a spacer and chemically links to a functional group of hyaluronic acid to afford said photoreactive hyaluronic acid derivative andsaid mutual photoreactive crosslinking groups of said photoreactive hyaluronic acid derivative are dimerized by irradiation with ultraviolet rays to form a cyclobutane ring and to thereby form said network structure.