摘要目的 探讨异硫氰酸荧光素(FITC)标记的神经生长因子缓释微球的制备,并对其进行体内外评价.方法 采用水-油-水的双乳化技术制备FITC标记的神经生长因子缓释微球.利用扫描电镜和荧光显微镜对其形态特征进行观察,并对其体内外释放情况进行研究.结果 制备的FITC标记的神经生长因子缓释微球包封率和载药量分别为(97.9±8.9)%和(4.90±0.56)%.扫描电镜结果显示所制备的微球呈圆形、形态规整、粒径分布较均匀.荧光显微镜结果显示所包载的蛋白类药物在微球内旱随机分布.缓释微球体外持续释放5周后,有73%的蛋白释放出来;荧光示踪显示在体内能够持续释放达5周以上.结论 采用水-油-水的双乳化技术制备的缓释微球可以将生物大分子药物如神经生长因子成功运载到脑内.

abstractsObjective To prepare and evaluate fluorescein isothiocyanate (FITC)-labelled recombinant human nerve growth factor(rhNGF) microspheres in vitro and in vivo. Methods FITC-labelled rhNGF microspheres were prepared by double emulsion (W1/O/W2) method. The characterization of FITC-labelled rhNGF microspheres was determined by scanning electronic microscopy and fluorescent microscopy.Then, the rhNGF release from FITC-labelled rhNGF microspheres was evaluated in vitro and in vivo. Results Encapsulation efficiency and protein loading of FITC-labelled rhNGF microspheres were (97.9±8.9)% and(4.90±0.56)% respectively. The FITC-labelled rhNGF microspheres have a spherical shape with asmooth surface under scanning electronic microscopy. The protein was encapsulated within the microsphere matrix with a random distribution pattern. After 5 weeks, 73% of protein was released in vitro. The release of protein was no less than 5 weeks in vivo. Conclusion The PLGA microspheres made by (W1/O/W2) method can be served as carrires for the delivery of biopharmaceutical macromolecular drugs, such as nerve growth factor, to the brain.