Patent ID: 8034382

Claim:
A method of preparing drug-containing microparticles comprising: dissolving a biodegradable polymer in organic solvent to form a polymer solution; dissolving or dispersing a drug in the polymer solution to form a polymer-drug-solvent phase; mixing the polymer-drug-solvent phase with an aqueous suspension comprising an inorganic gel to form a dispersion comprising polymer-drug droplets dispersed in the aqueous suspension, wherein the inorganic gel can be dissolved by acid, and the dispersion is essentially free of organic surfactants and organic emulsifiers; evaporating the organic solvent from the dispersion to convert the polymer-drug droplets to drug-containing microparticles; and recovering the drug-containing microparticles from the dispersion, wherein the step of recovering the drug-containing microparticles from the dispersion comprises adding acid to the dispersion to dissolve the inorganic gel.