Biodegradable particles, vascular occlusion material, and method for producing biodegradable particles
AssigneeToray Industries, Inc.
InventorsKazuhiro Tanahashi, Megumi Nakanishi, Yasufumi Yamamura, Masaki Fujita
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Abstract
Spherical biodegradable particles have improved flexibility, cause less aggregation among particles, and have improved particle shape-recovering ability after passing through a catheter or the like. The biodegradable particles include a synthetic polymer chemically cross-linked to a polyvalent carboxylic acid, the biodegradable particles having a water content of 20 to 90% in a water-saturated state.
Claims20
Biodegradable particles comprising a synthetic polymer chemically cross-linked to a polyvalent carboxylic acid, and having a water content of 20 to 90% in a water-saturated state.
A method of producing biodegradable particles comprising:
- a dissolving step wherein a synthetic polymer, polyvalent carboxylic acid and condensing agent are dissolved in an aprotic polar organic solvent having a dielectric constant of 35 to 50, to obtain Solution A;
- a droplet-forming step wherein said Solution A is added dropwise to a poor solvent for said aprotic polar organic solvent, to obtain droplets of Solution A;
- and
- a chemical cross-linking step wherein a chemical cross-linking reaction of said synthetic polymer is allowed to proceed in said droplets, to obtain biodegradable particles.
Biodegradable particles produced by:
- dissolving a synthetic polymer, polyvalent carboxylic acid and condensing agent in an aprotic organic solvent having a dielectric constant of 35 to 50;
- adding the obtained solution dropwise to a poor solvent for said aprotic polar organic solvent;
- and
- causing a chemical cross-linking reaction to proceed in the obtained droplets.
Dependencies are inferred from the claim text.