微柱离心高效液相法测定吉非替尼脂质体包封率

目的：建立测定吉非替尼脂质体包封率的微柱离心高效液相法。方法：采用Sephadex G-50制备的微型凝胶柱分离脂质体和游离药物，采用高效液相色谱法检测脂质体中的药物浓度和过柱前脂质体混悬液中的药物浓度，通过公式计算吉非替尼脂质体包封率。结果：洗脱曲线结果表明Sephadex G-50分离脂质体与游离药物的效果较好，最佳离心分离条件为2000r·min-1，3min，最佳洗脱方法为蒸馏水-硫酸铵混合洗脱，该法测定3批吉非替尼脂质体平均包封率为50.9%。结论：微柱离心高效液相法可以作为吉非替尼脂质体包封率测定的有效方法。

Determination of Entrap ment Efficiency of Gefitinib Liposomes by Mini-column Centrifugation Reversed phase High Performance Liquid Chromatography

Objective:To establish a mini-column centrifugation reversed phase high performance liquid chromatography to determine the entrapment efficiency of Gefitinib liposomes. Method: A mini-column centrifugation made by Sephadex G-50 was employed to separate the liposomes and the free drug. The entrapment efficiency of Gefitinib liposomes was measured in drug concentration enveloped in the liposomes and drug concentration before separation by reversed phase high performance liquid chromatography. Results: The elution curve suggested that the lioposome and free drug were well separated. The optimum of centrifugal separation was 2000r·min-1,3min.The optimum eluant was distilled water and ammonium sulfate. The average entrapment efficiency of three batches of Gefitinib liposomes was 50.9%.Conclusion:The method is applicable for the determination of entrapment efficiency of Gefitinib liposomes.