Patent ID: 6110503
Filing Date: 2000-08-29
Classification: A61K,A61P,B01J,Y10T

Abstract:
A microencapsulated active agent prepared by a method of preparing biodegradable, biocompatible microparticles, said method comprising:(A) preparing a first phase, said first phase comprising an active agent, a biodegradable, biocompatible polymer, and a solvent blend comprising a first solvent and a second solvent;(B) preparing a second phase, wherein said first phase is substantially immiscible in said second phase;(C) combining said first phase and said second phase under the influence of mixing means to form an emulsion in which said first phase is discontinuous and said second phase is continuous;(D) immersing said first phase and said second phase in a quench liquid that comprises a quench medium and a quantity of said first solvent, wherein said first solvent has a rate of extraction from said discontinuous first phase that is more rapid than a rate of extraction from said discontinuous first phase of said second solvent, said quench liquid being free from said second solvent;(E) isolating said discontinuous first phase in the form of microparticles; and(F) adjusting a temperature of said quench medium to control solubility of said first solvent in said quench medium.