Atkins T W, Peacock S J
Department of Pharmaceutical and Biological Sciences, Aston University, Birmingham, UK.
J Biomater Sci Polym Ed. 1996;7(12):1065-73. doi: 10.1163/156856296x00552.
Spherical microporous matrix type microspheres composed of 330 kD P(HB-HV) (10.8% HV) 20%PCL II containing a range of %BSA loadings have been fabricated using a single emulsion technique with solvent evaporation. Microspheres were generated in high yield (> 75%) and the percentage incorporation of BSA had no significant effect on microsphere size distribution, typically 6-50 microns in diameter with a mean of 26.28 +/- 2.34 microns, n = 25, for 20% BSA loaded microspheres. The loss of BSA both by partitioning into the aqueous continuous phase and through micropores generated during the precipitation of the fabrication polymer concomitant with solvent evaporation resulted in a low encapsulation efficiency (< 15%). When the total cumulative release of BSA was expressed as a percentage of the actual total BSA incorporated, BSA release was only marginally influenced by the theoretical percentage loading suggesting that the amount and duration of BSA release in vitro was initially influenced as much by micropore number and diameter as by the extent of matrix BSA loading and detectable levels of BSA release could be monitored for up to 24 days.
采用单乳液溶剂蒸发技术制备了由330 kD聚（3-羟基丁酸酯-3-羟基戊酸酯）（10.8% 3-羟基戊酸酯）和20%聚己内酯II组成的球形微孔基质型微球，其中含有一系列不同百分比的牛血清白蛋白负载量。微球的产率很高（> 75%），牛血清白蛋白的掺入百分比对微球尺寸分布没有显著影响，对于负载20%牛血清白蛋白的微球，其直径通常为6 - 50微米，平均直径为26.28 +/- 2.34微米，n = 25。牛血清白蛋白通过分配到水连续相中以及在制备聚合物沉淀过程中伴随溶剂蒸发产生的微孔而损失，导致包封效率较低（< 15%）。当牛血清白蛋白的总累积释放量表示为实际掺入的牛血清白蛋白总量的百分比时，牛血清白蛋白的释放仅受到理论负载百分比的轻微影响，这表明体外牛血清白蛋白释放的量和持续时间最初受到微孔数量和直径的影响与基质中牛血清白蛋白负载量一样大，并且可以监测到牛血清白蛋白释放的可检测水平长达24天。
