处方和工艺参数对盐酸昂丹司琼微球体外释放度的影响

目的：考察处方工艺参数对微球体外释放度的影响.方法：采用O/O型乳化溶剂挥发法,以乳酸-羟基乙酸共聚物为载体,制备盐酸昂丹司琼（Ondansetron hydrochloride,OND）微球.采用紫外分光光度法测定微球的体外释放度.结果：选择对OND具有较好溶解能力的混合溶剂为内油相溶剂,可以降低突释;增加理论载药量,延缓正己烷加入的时间和减小粒径可以增加OND微球的释药速度.结论：通过对处方和工艺的调节可使OND微球的体外释药曲线符合Higuchi方程,2周的累积释放量在80%左右.

Effects of formulation factors on release rate in vitro of ondansetron hydrochloride-loaded PLGA microspheres

Objective:To study the effects of formulation factors on in vitro release rate of ondan- setron hydrochloride (OND)-loaded microspheres.Methods:O/O emulsion solvent evaporation tech- nique was used to fabricate OND-loaded poly(lactic-co-glycolic acid) microspheres.Ultraviolet spectro- photometry was applied to determine drug release rate.Results:Initial burst release was reduced by u- sing a solvent that is hypersoluble to OND as internal phase solvent.Formulation factors to effect drug re- lease rate included increase of the weight ratio of drug to PLGA,postponement of the hexane addition and decrease of the particle size.The release of OND from PLGA microspheres was sustained up to 80% for 2 weeks.The release profile in vitro obeyed the Higuchi equation.Conclusion:The effect of formulation factors on release rate in vitro of OND from PLGA microspheres is evident.