LOW RESIDUAL SOLVENT MICROSPHERES AND MICROENCAPSULATION PROCESS

摘要

This invention is the process for the preparation of microcapsules with a reduced residual solvent level, having a core compound encapsulated by a polymer coating which comprises, dissolving the polymer in an organic solvent in which the core compound is not soluble; adding the core compound; adding a first non-solvent of the polymer and core material selected from synthetic oil or vegetable oil in a ratio of first non-solvent to organic solvent of from about 1.5:1 wt/wt to about 2.5:1 wt/wt to form microcapsules; and adding a second non-solvent of the polymer. The invention is also directed to microcapsules comprising a core compound encapsulated by a polymer coating, with the microcapsule having a residual solvent content of less than one percent. The invention is particularly useful for encapsulating pharmaceutical materials in biodegradable polymers.