目的 研究齐墩果酸纳米粒（OA-NP）在小鼠体内的分布及靶向性。方法 采用纳米沉淀法制备OA-NP，经小鼠尾静脉给药，采用HPLC内标法检测齐墩果酸（OA）在小鼠主要脏器（心、肝、脾、肺、肾）中的浓度随时间的变化，并与OA溶液对照组进行比较，以峰浓度比（Ce）和相对摄取率（Re）评价其靶向性。结果 OA-NP组在各脏器中的浓度明显高于OA溶液对照组，其靶向性顺序依次为：肝 ＞ 脾 ＞ 肺 ＞ 肾 ＞ 心，并且肝中的药物浓度显著高于其他脏器。结论 OA-NP能明显改变OA在小鼠体内的组织分布，尤其具有理想的肝靶向性。

Objective To study the distribution and targeting of oleanolic acid nanoparticles（OA-NP） in rats. Methods The nanoparticles were prepared by nanoprecipitation method. After caudal intravenous injection，the contents of oleanolic acid in rat heart，liver，spleen，lung and kidney were detected by internal standard HPLC. The indexes of peak concentration ratio（Ce） and relative uptake rate（Re） were used to evaluate the targeting feature of OA-NP. Results The tissue concentration of OA in various organs of OA-NP group was significantly higher than that of OA solution. The targeting sequence was liver＞spleen＞lung＞kidney＞heart，and the concentration in the liver was significantly higher than that of other organs. Conclusion The tissue distribution of OA-NP differs from OA in mice，and OA-NP has ideal liver targeting in particular.

R285.5

广东省科技计划项目（20120318055）；广东省教育厅学科建设专项资金（2013KJCX0110）。