壳聚糖装载猪胸腺肽微球给药

目的：以猪胸腺肽为芯材、壳聚糖为壁材，采用乳化交联结合单凝聚法制备猪胸腺肽壳聚糖口服微球。方法：以壁材浓度、交联剂含量、油水比值、芯材壁材比值为四因素设计正交实验，确定微球最佳制备条件，并对其体外释放及稳定性进行研究。结果：制备微球最优化条件为壳聚糖浓度1％、25％戊二醛含量7％、油水比值2：1、壳聚糖与胸腺肽比值1：1；微球在pH1．5的HC1溶液中2h释放30％，在pH6．8及7．4的PBS缓冲液中最终释放度约80％，并在24h达到释放终点；微球30rain突释率约为10％，1h释放率约为20％，其后缓慢而持续地释放；猪胸腺肽壳聚糖微球在0℃保存8个月时微球外观及形态没有差异，药物剩余率约为91．8％。结论：采用乳化交联结合单凝聚法制备的猪胸腺肽壳聚糖口服微球为缓释给药系统的临床应用奠定了理论基础，具有重要的实际应用价值和社会意义。

Chitosan Loaded Pig Thymosin Microspheres for Drug Delivery

Objective： Using chitosan as shell materials and pig thymosin as core materials, to prepare thymosin microspheres through W/O emulsion cross-linking method combined with simple coacervation. Methods： In order to determine the best preparation condition and conduct studies on release and stability of thymosin-loaded chito- san microspheres in vitro, orthogonal experiment was designed based on four factors, including the concentration of chitosan, quantity of glutaraldehyde, oil/water ratio, and chitosan/thymosin ratio. Results： The best preparation con- dition was as follows： 1% chitosan, 7% glutaraldehyde （25% ）, 2：1 oil/water, 1：1 chitosan/thymosin. The release rate of microspheres was 30% in 2 h with pill.5 HC1, and ultimately reached to 80% in 24 h with pH6.8 as well as pH7.4 in PBS buffer solution. The burst release rate was about 10% in 30 min and release rate reached to 20% in 1 h, and thenceforth the microspheres exhibited a slow and sustaining release rate. The appearance and shape of the microspheres hadn＇t changed significantly stored at 02： for 8 months and the remaining rate of drug was 91.8%. Conclusion： Thymosin microspheres prepared through W/O emulsion cross-linking method combined with simple coacervation has important practical values and social significances, laying a theoretical founda- tion for the clinical application of slow-release drug delivery system.