微柱离心结合氯化银胶体散射光猝灭法测量牛血清白蛋白脂质体中的痕量蛋白质

The novel analytic method used for measuring encapsulation efficiency of bovine serum albumin liposome

目的：运用DEAE-Sephadex A50微柱离心法结合Agcl胶体溶液散射光强度猝灭法测定BSA脂质体的包封率。方法：以BSA为模型药，采用逆向蒸发法制备脂质体；建立DEAE-SephadexA50微柱离心分离游离蛋白质和脂质体的方法，并结合AgCl胶体溶液散射光强度猝灭法测定脂质体包封率。结果：AgCl胶体溶液散射光强度猝灭法中能达到散射光强度和散射光猝灭效果的最佳Cl^-与Ag^＋摩尔比为1，选择反应体系为pH值4．8的醋酸-醋酸钠缓冲液，反应时间在50-80min较好，本实验中的反应时间为60min，不同的环境温度对测定结果有不可忽略的差异，应始终保证在同一环境温度下测定。本法的平均柱回收率为97．78％，RSD为0．18％（n=4），柱分离效率90％，柱分离效果较好，可以适用于游离蛋白与脂质体的分离和检测。结论：用DEAE-Sephadex A50微柱离心结合AgCl胶体溶液散射光强度猝灭法测定包封率的方法，可适用于给药剂量较低的蛋白质类药物脂质体包封率测定过程中痕量蛋白质的检测。

OBJECTIVE Ovine serum albumin （BSA） liposome was prepared, and the encapsulation efficiency （EE） was measured. METHODS Liposome and free BSA were separated through DEAE-Sephadex AS0 minicolumn centrifuge, EE was determined by the analytic method of peptide by quenching of scattering light of silver chloride gel. RESULTS The pH of reaction buffer system is 4. 8, reaction time in the experiment is preferred to 60 rain, and the measurements should be performed under the same conditional temperature in the method of quenching of scattering light of silver chloride gel. In the method of DEAE-Sephadex A50 minicolumn centrifuge, the minicolumn recovery（ % ）is 97. 78 %, RSD is 0.18 % （n = 4）, and the division efficiency minicolumn〉90% （n = 4）. CONCLUSION The analytic method of encapsulation efficiency （EE） was established through DEAE-Sephadex A50 minicolumn centrifuge combined quenching of scattering light of silver chloride gel method.