目的 建立盐酸阿霉素和知母皂苷AⅢ共载脂质体包封率的测定方法。方法 采用薄膜分散法制备盐酸阿霉素和知母皂苷AⅢ共载脂质体，分别用透析法、微柱离心法和超高速离心法分离脂质体和游离药物，采用HPLC法测定游离药物含量和脂质体中的药物含量，计算得出盐酸阿霉素和知母皂苷AⅢ的包封率。结果 确定盐酸阿霉素和知母皂苷AⅢ共载脂质体处方为DPPC-DSPE-PEG2000-TAⅢ-DOX比例为5：1：1：1，采用薄膜分散法制备的脂质体大小适中，粒径为（55.4±0.40） nm，PDI为0.20±0.02，电位为（-17.4±0.6） mV；在所选的色谱条件下，脂质体的其他组分不干扰样品的测定，盐酸阿霉素在24.9~498.0μg/mL（r=0.999 9），知母皂苷AⅢ在50.55~1 011.00 μg/mL（r=0.999 6）线性关系良好。研究结果表明微柱离心法能有效地将盐酸阿霉素和知母皂苷AⅢ双载脂质体与游离药物分离，测得的包封率分别为（85.12±1.27）%、（76.51±0.46）%。结论 薄膜分散法可用于盐酸阿霉素和知母皂苷AⅢ共载脂质体的制备；微柱离心法准确度高、重复性好并快捷方便，可用于包封率的测定。

Objective To develop a method to determine the encapsulation efficiency of doxorubicin hydrochloride and timosaponin AⅢ co-loaded liposomes.Methods In this paper, the thin-film rehydration method was used to prepare doxorubicin hydrochloride and timosaponin AⅢ co-loaded liposomes. Liposomes and free drugs were separated by dialysis, gel microcolumn centrifugation, and ultra-high speed centrifugation. The content of free drugs and drugs in liposomes was determined by HPLC, and the entrapment efficiency of doxorubicin hydrochloride and timosaponin AⅢ co-loaded liposomes was calculated.Results The optimal formulation of doxorubicin hydrochloride and timosaponin AⅢ co-loaded liposomes was DPPC-DSPE-PEG2000-TAⅢ-DOX with a molar ratio of 5:1:1:1. The liposomes prepared using thin-film rehydration method had a well-defined spherical shape with a size of (55.4 ±0.40) nm, a PDI of (0.20 ±0.02), and a weakly negative zeta potential of (-17.4 ±0.6) mV. The excipients in the liposomal formulation can be well separated from doxorubicin hydrochloride and timosaponin AⅢ in the selected chromatographic conditions. The calibrated linear curve of doxorubicin hydrochloride was within 24.9-498.0 μg/mL (r=0.999 9) and that of timosaponin AⅢ was within 50.55-1 011.0 μg/mL (r=0.999 6). Free doxorubicin hydrochloride and timosaponin AⅢ were well separated from liposome by gel microcolumn centrifugation, and the encapsulation efficiency of doxorubicin hydrochloride and timosaponin AⅢ was (85.12 ±1.27)% and (76.51 ±0.46)% respectively.Conclusion The thin-film dispersion-method can be used for the preparation of doxorubicin hydrochloride and timosaponin AⅢ co-loaded liposomes. The method of gel microcolumn centrifugation is accurate, reproducible, simple, and suitable for determination of the encapsulation efficiency of co-loaded liposomes.

国家自然科学基金资助项目（81403175）；上海卫生局项目（2017YQ072，201740152）；上海博士点基金资助项目（B201703）