摘要
目的评价不同制备工艺对胶质细胞源性神经营养因子（glial cell linederived neurotrophic factor，GDNF）缓释微球的影响及微球所包裹的GDNF生物学活性。方法以聚乳酸-羟基乙酸共聚物（polylactide—CO—glycolide，PLGA）为包裹材料，采用复乳法（WI／O／W2）制备GDNF—PLGA微球，通过两因素析因设计方差分析，研究PLGA中乳酸（LA）与羟基乙酸（GA）单体组成比例和复乳搅拌速度对GDNF微球的粒径、包封率、突释率和体外释放行为的影响，并用PC-12细胞检测微球所释放的GDNF生物学活性，确定最佳制备工艺。结果PLGA的单体组成比例可影响微球的突释率（P〈0．05），对粒径和包封率的影响无统计学意义，随着GA比例的增加，微球中GDNF释放速度加快。复乳搅拌速度由1000r／min增加到3000r／min后，微球的粒径显著减小（P〈0．01），突释率显著增加（P〈0．01），体外释放更为快速。微球中的GDNF在37℃下活性有效期可达20d左右，较单独存放的GDNF活性有效期延长10d以上。结论复乳法可制备具有较高包封率和适宜体外释放时间的GDNF缓释微球，且活性有效期延长。
Objective To evaluate the effect of different preparation processes on preparation of the glial cell fine-derived neurotrophic factor （GDNF） loaded microspheres and observe the biological activity of GDNF. Methods With polylactide-co-glycolide （PLGA） as the coating material, the GDNFloaded mierospheres were prepared by using double emulsion （W1/O/W2）. Two-factor factorial design variance analysis was clone to analyze the effects of the composition proportion of lactic acid （ LA ） and glycolic acid （GA） in PLGA and the stirring speed of multiple emulsion on particle size, entrapment effi- ciency, burst release and in vitro release characteristics of the GDNF-loaded mierospheres. PC-12 bioassay was employed to detect the biological activity of the released GDNF so as to determine the optimal preparation process. Results The composition proportion of PLGA could affect the microspheres＇ burst release （ P 〈 0.05 ） , with no effect on particle size and entrapment efficiency, with the higher. With higher proportion of GA, the release speed of GDNF in the microspheres was increased. When the stirring speed of multiple emulsion was increased from 1 000 r/min to 3 000 r/min, the particle size of the microspheres was decrease significantly （ P 〈 0.01 ）, the burst release was increased markedly （ P 〈 0. 01 ） and the in vitro release rate was accelerated. The activity of GDNF in the mierospheres could last for about 20 days at 37℃, which was 10 days longer than that of single GDNF. Conclusions Double emulsion can prepare the GDNF-loaded microspheres with high entrapment efficiency and suitable in vitro release time. In the meantime, the microspheres can extend the validity of GDNF.
出处
《中华创伤杂志》
CAS
CSCD
北大核心
2011年第2期170-174,共5页
Chinese Journal of Trauma
基金
基金项目：浙江省教育厅资助项目（20070904）
温州市科技局对外合作资助项目（H20080031）
