Spheric polycaprolactone ( P C L) microparticles were prepared by P C L polymerwith an emulsification solvent evaporation technique . Effects of various stabilizers,such asgelatin ,hydrophobically modified polyacrylamide derivative ( P A M) and poly(vinyl alcohol)( P V A) on the morphology and particle size distribution of the P C L microparticles werestudied. The degradation behaviors of the P C L microparticles were compared with andwithoutlipase under p H7 .4 at 37 ±1 ℃. Theresultsshowed thatin the case of using gelatinas a stabilizerthe diameter of the P C L microparticles was in a range of 13 .4 ±4 .7μm . Thefactthat the degradation rate of the P C L microparticles was accelerated in the presence ofenzyme———lipase was evidenced by S E M and G P C measurements. On the other hand ,according to S E M,interference contrast microscopy and X ray diffraction techniques,it wasevidenced that the degradation ofthe P C Lmicroparticlesstarted in theamorphous area ofthe P C L microparticles.
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