漆黄素脂质体的制备及其质量评价

目的: 制备漆黄素脂质体，并对其进行制剂学研究及体内外评价。方法：采用薄膜分散法制备漆黄素脂质体，以粒径为指标，通过单因素考察，制备不同磷脂与胆固醇总量、不同磷脂胆固醇比例及不同药脂比的漆黄素脂质体，确定漆黄素脂质体最优处方。采用激光散射粒径仪测定漆黄素脂质体的粒径、多分散系数、Zeta电位；采用超滤离心法测定漆黄素脂质体的包封率和载药量；对漆黄素脂质体的稳定性，在3种释放介质（pH 1.2 盐酸、双蒸水和pH 7.4 磷酸盐缓冲液）中的体外释放情况，细胞毒性以及药物代谢动力学等体内外参数进行评价。 结果：采用最优处方（漆黄素22.2 mg、磷脂133.3 mg、胆固醇16.7 mg、胆酸钠110 mg、肉豆蔻酸异丙酯60 mg）制备的漆黄素脂质体平均粒径为(60.32±1.08)nm，多分散系数为0.198±0.011，包封率为(94.37±0.62)%，载药量为(4.500±0.021)%。透射电镜结果显示漆黄素脂质体外形圆整且分布均匀。制成脂质体后可提高漆黄素原料药的溶解度、体外释放率以及相对生物利用度；漆黄素脂质体在30 d内具有较好的稳定性。漆黄素脂质体对人肝癌HepG2细胞有明显的增殖抑制作用，且呈现剂量依赖关系。结论：漆黄素脂质体能显著提高难溶性药物漆黄素的溶解度和生物利用度。

Preparation and quality evaluation of fisetin-loaded liposomes

Objective: To develop and optimize the preparation protocols of fisetin liposomes, and to evaluate in vitro and in vivo the properties of liposomes obtained. Methods: Fisetin liposomes were prepared by film dispersion method. Taking the particle size as the index,fisetin liposomes with different total phospholipid and cholesterol, phospholipid cholesterol ratio and different drug lipid ratio were prepared to determine the optimal formulation through single factor analysis. The particle size, polydispersity coefficient and zeta potential of fisetin liposomes were measured by laser scattering particle size meter. The entrapment efficiency and drug loading were determined by ultrafiltration centrifugation.The stability, in vitro release in three media (pH 1.2 hydrochloric acid, double distilled water, pH 7.4 phosphate buffer), cytotoxicity and pharmacokinetics were also evaluated. Results:  The average particle size of fisetin liposomes prepared with the optimal formulation (fisetin 22.2 mg, phospholipid 133.3 mg, cholesterol 16.7 mg, sodium cholate 110 mg and isopropyl myristate 60 mg) was about (60.32±1.08)nm, the polydispersity coefficient was 0.198±0.011, the entrapment efficiency was (94.37±0.62)%, and the drug loading was (4.500±0.021)%.The results of transmission electron microscope showed that the liposomes were round and uniformly distributed in vitro; The solubility, in vitro release rate and relative bioavailability of fisetin could be improved in prepared liposomes; Fisetin liposomes showed good stability within 30 days. Furthermore, fisetin liposomes significantly inhibited the proliferation of human hepatoma HepG2 cells in a dose-dependent manner. Conclusion:  Fisetin liposomes can significantly improve the solubility and bioavailability of fisetin. ［Key words］fisetin；liposomes；in vitro and in vivo evaluation；insoluble drug；formulation development