微柱凝胶联合高效液相色谱法同时测定双载药脂质体中阿霉素与他莫昔芬的包封率

目的：建立双载药脂质体中阿霉素（DOX）与他莫昔芬（TAM）包封率的测定方法。方法：采用Sephadex LH-20分离载药脂质体与游离药物。采用HPLC法梯度洗脱，测定脂质体中装载药物的含量及脂质体制备时加入的药物总量，计算脂质体中DOX与TAM的包封率。结果：在所选择的色谱条件下，DOX与TAM的专属性良好。DOX与TAM分别在4.68~37.44，4.80~38.40 μg·mL^-1范围内线性关系良好。流出曲线研究结果表明，Sephadex LH-20微柱法能有效分离载药脂质体与未包载的游离药物，游离药物DOX与TAM的柱回收率分别为98%~102%、99%~101%。微柱凝胶分离-HPLC法测定得，双载药脂质体中DOX与TAM的含量均约为1 mg·mL^-1，包封率均>90%。结论：该方法简便快速、精密可靠，可应用于双载药脂质体中DOX与TAM含量与包封率的测定。

Simultaneous determination for the co-encapsulation efficiencies of doxorubicin and tamoxifen in liposomes by gel filtration combined with HPLC method

OBJECTIVE To develop a gel filtration combined with HPLC method for determining the co-encapsulation efficiencies (EE) of doxorubicin (DOX) and tamoxifen (TAM) in liposomes. METHODS DOX/TAM loaded liposomes were separated from free drug by Sephadex LH-20. Then, the DOX and TAM loading were analyzed using a HPLC method. The EE of DOX and TAM were calculated as the amount of liposomal drug and the total amount of drug added initially. RESULTS Under the selected chromatographic conditions, DOX and TAM had good specificities. The concentrations of DOX and TAM had good linear correlations in the ranges of 4.68-37.44 μg·mL^-1 and 4.80-38.40 μg·mL^-1, respectively. The elution profile showed that drug loaded liposomes had a good separation with free drug. The column recoveries of DOX and TAM were 98%-102% and 99%-101%, respectively. Both the amounts of DOX and TAM in liposomes were approximately 1 mg mL^-1 and the EE of DOX and TAM in liposomes were all >90% by gel filtration combined with HPLC method. CONCLUSION This simultaneous determination by gel filtration combined with HPLC method is dependable, simple and practical, which may be available for determining the co-encapsulation efficiencies of doxorubicin and tamoxifen in liposomes.