Patent ID: 6440493
Filing Date: 2002-08-27
Classification: A61K,B01J,Y10T

Abstract:
A method for making microparticles, the method comprising(a) preparing a first phase comprising a solution of an excipient dissolved in a first solvent; (b) preparing a second phase comprising (i) a second solvent which is totally or partially immiscible in the first solvent, and (ii) a surfactant; (c) preparing an extraction phase comprising a third solvent which is a nonsolvent for the excipient, a solvent for the second phase, and a solvent for the first solvent, wherein the first solvent has a solubility in the extraction phase of between about 0.1% and 25% by weight; (d) mixing the first phase and the second phase to form an emulsion having microdroplets comprising the first phase; (e) mixing a portion of the extraction phase in the emulsion in an amount sufficient to initiate hardening of the microdroplets, thereby forming microparticles; and (f) evaporating from the microparticles substantially all of the solvent remaining in the microparticles following step (e).