EXTRACTION OF SOLVENT FROM BIODEGRADABLE MICROPARTICLES Russian patent published in 2019 - IPC A61K9/16 A61K9/50 A61K38/28 A61K38/26 A61K47/30 B01J13/12 B01D11/04 

FIELD: chemistry.

SUBSTANCE: described is a method for reducing concentration of a solvent in a plurality of biodegradable microparticles. Method involves contacting a mixture containing a plurality of microparticles and a solvent with water to form an aqueous suspension. First portion of the solvent is dissolved in water of the aqueous suspension while reducing the concentration of the solvent in the plurality of microparticles from the first concentration of the solvent in the mixture to the second concentration of the solvent in the aqueous suspension. Further, the aqueous suspension is transferred into a concentration device which further reduces the concentration of the solvent from the second solvent concentration to the third solvent concentration. Then, concentrate of microparticles with third concentration of solvent is transferred to flushing device to form amalgam of washed microparticles with fourth concentration of solvent with subsequent drying of amalgam of washed microparticles. Biodegradable microparticles of the invention contain poly(lacto-co-glycol) acid, the solvent in the biodegradable microparticles contains a halogenated organic solvent, preferably methylene chloride. Described also is a system for reducing concentration of a solvent in a plurality of biodegradable microparticles. Microparticles according to the invention can contain a therapeutically active agent, preferably pegylated insulin.

EFFECT: disclosed method reduces concentration of solvent in multiple biodegradable microparticles to 0_03 % by weight or less.

42 cl, 4 dwg