INCORPORATION AND RELEASE OF VANCOMYCIN FROM POLY(D,L-LACTIDE-CO-GLYCOLIDE) MICROSPHERES

Spherical monolithic microspheres, with a honeycomb-like internal arch itecture, composed of PLCG 50:50 and PLCG 75:25 and containing a range of vancomycin loadings, have been fabricated using a W/O emulsificati on with solvent evaporation technique. Microspheres were generated in high yield (80 wgt%) and vancomycin incorporation, confirmed using the displacement of DSC thermograms, had no significant effect on microsp here size distribution (5-50 mu m). The vancomycin encapsulation effic iency was high (>64%) and release profiles were characterized by a sub stantial initial burst release and a subsequent low-level sustained re lease extending up to 30 days depending upon the fabrication polymer, % vancomycin loading and incubation medium used. In both Hank's buffer and newborn calf serum the mean total cumulative release of vancomyci n from microspheres increased significantly with theoretical percentag e loading.