Preparation of OANO-1 polylactic acid microspheres

OBJECTIVE To optimize the preparation conditions of “OANO-1” polylactic acid microspheres by orthogonal test. METHODS “OANO-1” polylactic acid microspheres were made by W/O/W-liquid drying process. The orthogonal test design was used to optimize the technology of preparation. The surface morphology of the microspheres was observed by SEM. The microsphere formation was confirmed with DSC. The mean diameter and the size distribution of microspheres, the drug loading,the incorporation efficiency,the reappearances of pharmaceutical technology were examined. RESULTS The “OANO-1” microspheres were regular in their morphology. Drug was enveloped in microspheres but not physically mixed with PLA. The average particle size was 8.59μm with over 90% of the microspheres being in the range of 1～12μm. The drug loading and the incorporation efficiency were 48.39% and 19.32% respectively. CONCLUSION The optimized preparation conditions of “OANO-1” polylactic acid microspheres is obtained.