MODIFIED HYALURONIC ACID, ITS PRODUCTION AND SUSTAINED RELEASE PHARMACEUTICAL PREPARATION USING THE SAME

• Main Authors: YAMAGUCHI MICHIHIRO, AKIMA KAZUO, MATSUZAKI FUMIO, HARIKI TOSHIO
• Format: Patent
• Language: English
• Published: 25.01.1994
• Edition: 5
• Subjects: CHEMISTRY; COMPOSITIONS BASED THEREON; DERIVATIVES THEREOF; HUMAN NECESSITIES; HYGIENE; MEDICAL OR VETERINARY SCIENCE; METALLURGY; NUCLEIC ACIDS; NUCLEOSIDES; NUCLEOTIDES; ORGANIC CHEMISTRY; ORGANIC MACROMOLECULAR COMPOUNDS; POLYSACCHARIDES; PREPARATIONS FOR MEDICAL, DENTAL, OR TOILET PURPOSES; SUGARS; THEIR PREPARATION OR CHEMICAL WORKING-UP

PURPOSE:To obtain a modified hyaluronic acid, capable of retarding the biodegradation rate without impairing the bio-compatibility and useful as a sustained release pharmaceutical preparation by binding an alcoholic hydroxyl group of the hyaluronic acid to a low-molecular weight water-soluble organic acid through ester bond. CONSTITUTION:The modified hyaluronic acid of the formula (R1 to R4 are H or low- molecular weight water-soluble organic acid residue, bound through ester bond and present in the living body; R5 is H or alkali metallic atom) is obtained by suspending powdery hyaluronic acid in a low-molecular weight water-soluble organic acid (preferably pyruvic acid and/or lactic acid) in a free state present in the living body, adding trifluoroacetic anhydride thereto and carrying out the reaction. The sustained release pharmaceutical preparation is obtained by chemically or physically supporting a medicine requiring the sustained release (e.g. an antibiotic substance, an antimicrobial agent or a vitamin preparation) on the modified hyaluronic acid. This modified hyaluronic acid is capable of moderately regulating the degradability thereof in the living body and producing the excellent sustained release pharmaceutical preparation without impairing the bio-compatibility essentially possessed by the hyaluronic acid.