激光共聚焦显微镜分析载蛋白微球的结构及药物分布

Structure analysis and drug distribution of microspheres loaded protein drug by confocal laser scanning microscopy

目的:采用激光共聚焦显微镜(CLSM)表征微球,获得微球内部药物分布及结构信息。方法:分别以异硫氰酸荧光素牛血清白蛋白(FITC-BSA)和牛血清白蛋白(BSA)为蛋白模型药物,采用复乳化法制备聚酯类聚合物微球。运用CLSM对载FITC-BSA的微球扫描成像,进行图像分析和三维重建;并通过CLSM考察载BSA微球对异硫氰酸荧光素(FITC)的摄取,研究微球突释。结果:CLSM实现微球内部药物分布的可视化及其三维重构,并检测药物分布均匀性。摄取实验表明,在释放初期,包载药物很可能通过与微球表面相连接的孔洞扩散释放,造成突释。结论:CLSM可观察微球内部药物分布及结构。

OBJECTIVE To visualize microstructure and drug distribution within microspheres by confocal laser scanning microscope （CLSM）. METHODS Fluorescein isothiocyanate labelled bovine serum albumin （FITC-BSA） and bovine serum albumin （BSA） were used as hydrophilic model drugs, aliphatic polyesters microspheres were prepared using a double-emulsion technique. By applying CLSM, drug distribution was visualized, and three-dimensional reconstruction and image analysis of mierospheres were performed. Moreover, uptake experiment was carried out by using CLSM to analyze burst release. RESULTS CLSM allowed visualization and three-dimensional reconstruction of drug distribution within microspheres. And homogeneity of drug distribution could also be investigated. In addition, uptake experiment revealed that encapsulated molecules were presumably dumped out through pores connected with external medium, which may be the cause of burst release. CONCLUSION CLSM allows inspection of drug distribution and internal structures of microspheres.