载10-羟基喜树碱超声微泡的制备、表征及其体外超声成像特性

Preparation,characteristics of imaging and in vitro release of 10-hydroxycamptothecin-loaded microbubbles

目的 制备载10-羟基喜树碱缓释超声微泡,并考察其体外释药特性和体外超声成像特性.方法 以高分子多聚物聚乳酸为材料,以W/O/W型乳化溶剂挥发法制备载羟基喜树碱超声微泡.结果 扫描电子显微镜观察载10-羟基喜树碱超声微泡具有明显的球状结构;粒度分布在0.45 ～ 5.12 μm之间;采用荧光分光光度法测定其载药量和包封率分别为（4.10±1.29）％和（67.44±2.55）％;体外释放可持续48 h,累积释放率达到60％;此外,体外超声成像显示微泡具有良好的反射超声信号能力.结论 载羟基喜树碱超声微泡可以作为造影剂进行药代动力学的研究.

AIM To prepare 10-hydroxycamptothecin （HCPT） -loaded microbubbles, and to determine the profiles of its encapsulation efficiency, in vitro release, and ultrasound imaging. METHODS HCPT-loaded mi- crobubbles was prepared through W/O/W double emulsion technique with polylactic acid （PLA） as the material. RESULTS Laser scanning microscope was for observation of the encapsulation of the microbubbles with particle sizes ranging from 0. 45 μm to 5.12 μm. The encapsulation efficiency and HCPT-loading content were determined by fluorescence spectrophotometry and were measured to be （67.44 ± 2.55 ）% and （4. 10 ± 1.29 ）% , respective- ly. The in vitro release data showed that total 60% of HCPT was continuously released from the HCPT-loaded mi- crobubbles within forty-eight hours. HCPT-loaded microbubbles also displayed a good ultrasound reflection ability through in vitro ultrasound imaging. CONCLUSION HCPT-loaded microbubbles can be applied as a contrast medium for the pharmacokinetics study.