Patent ID: 8329856

Claim:
A method for preparing a biodegradable polymer microparticle, comprising the steps of: (a) dissolving a biodegradable polyester-based polymer in DMSO (Dimethyl Sulfoxide) to form a solution; (b) spraying the solution in a hydrocarbon solution having 5 to 10 carbon atoms (C5 to C10) at a temperature of higher than −20° C. to less than a melting point of DMSO to provide a microparticle, wherein the hydrocarbon solution is phase-separated from DMSO and is selected from the group consisting of pentane, hexane, heptane, octane, nonane, decane and petroleum ether; (c) adding the microparticle in a salt aqueous solution to dissolve the DMSO in the solution and remove the DMSO; and (d) removing the salt from the microparticle.