Extraction process for producing PLGA microspheres
US5705197A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 16, 1996 |
| Grant date | Jan 6, 1998 |
| Priority date | — |
| Expiry date | Aug 16, 2016 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K2039/55555
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
A hybrid evaporation-extraction process for preparing microspheres of a p(DL-lactide-to-glycolide) biodegradable polymer, comprising: PA1 a. preparing a lyophilized biologically active material-sucrose matrix; adding acetonitrile solvent to biologically active material-sucrose matrix to form a solution; PA1 b. preparing a solution of a biodegradable poly (DL-lactide-co-glycolide) polymer by adding acetonitrile solvent to the polymer; PA1 c. adding the biodegradable poly (DL-lactide-co-glycolide) polymer acetonitrile solution to the biologically active material-sucrose acetonitrile solution; PA1 d. adding with stirring an oil containing lecithin to the poly (DL-lactide-co-glycolide) polymer-sucrose-biologically active material solution to evaporate acetonitrile and form an emulsion containing microspheres of poly (DL-lactide-co-glycolide) biodegradable polymers; PA1 e. adding the emulsion from step d. into a solvent selected from heptane, hexane, pentane or isopropanol; and PA1 f. collecting microspheres of poly (DL-lactide-co-glycolide) biodegradable polymers of from 1.0 to about 10.0 micrometers after filtration and washing with a fresh solvent selected from heptane, hexane, penta…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.