可控性释放NGF的京尼平- 壳聚糖微球的研究

目的:在体外研究京尼平-壳聚糖微球可控性释放具有生物活性的神经生长因子的可行性。方法:采用"乳化-化学交联"技术制备包埋神经生长因子的京尼平-壳聚糖微球,京尼平为化学交联剂;应用扫描电镜、粒径分布、体外缓释动力学及细胞生物活性分别对微球的性能进行研究。结果:京尼平-壳聚糖微球表面光滑,平均粒径在5.1~50.5μm之间;京尼平的浓度可影响微球在体外释放神经生长因子的速度,经高浓度京尼平交联的微球能减缓并持续释放神经生长因子;此外,从京尼平-壳聚糖微球释放的神经生长因子可维持PC12细胞的生物活性,提高NGF生物利用率。结论:京尼平-壳聚糖微球能有效缓释具有生物活性的NGF超过14天,为神经退行性疾病的治疗提供一种治疗策略。

Study on Genipin-chitosan Microspheres for the Controlled Release of Nerve Growth Factor

Objective:To investigate the feasibility of the controlled release of bioactive nerve growth factor (NGF) with genipin-chitosan microspheres in vitro.Methods:The genipin-chitosan microspheres were prepared by the emulsion-chemical cross-linking method with genipin as a chemical cross-linking agent. Scanning electron microscopy, the size and distribution, release tests in vitro and bioactivity assay were subsequently evaluated to study the functions of the microspheres.Results:The genipin-chitosan microspheres had smooth surfaces with mean sizes between 5.1 and 50.5 um. The in vitro release profiles of NGF from genipin-chitosan microspheres were influenced by the concentration of genipin. Genipin-chitosan microspheres were cross-linked with higher concentration of genipin, which showed slower and sustained release of NGF. In addition, the released NGF from genipin-chitosan microspheres was capable of maintaining the viability of PC12 cells and improving the biological utilization of NGF.Conclusion:Our findings suggest that NGF-loaded genipin-chitosan microspheres are capable of releasing bioactive NGF over 14 days, and the result provide potential treatment strategy in neurodegenerative disorders.