盐酸伊立替康脂质体的制备及包封率的测定

目的制备盐酸伊立替康脂质体,建立包封率测定方法。方法采用乙二胺四乙酸铵梯度法制备盐酸伊立替康脂质体;以阳离子交换树脂离心法分离脂质体和游离药物;采用紫外可见分光光度法测定脂质体包封率。结果阳离子交换树脂柱对质量浓度为1.0~2.4 g.L-1伊立替康能够完全吸附,且对空白脂质体无吸附,空白脂质体回收率达99.73%;采用紫外可见分光光度法测定盐酸伊立替康含量,在372 nm波长下,空白辅料对药物测定无干扰,盐酸伊立替康质量浓度在2.5~45.0 mg.L-1内线性关系良好(r=0.999 9),精密度和回收率均符合要求;盐酸伊立替康脂质体包封率为95.4%。结论乙二胺四乙酸铵梯度法适用于制备盐酸伊立替康脂质体,所建立的分析方法简单快速,准确可靠,可用于盐酸伊立替康脂质体包封率的测定。

Preparation of irinotecan hydrochloride liposomes and quantification of its entrapment efficiency

Objective To prepare irinotecan hydrochloride(CPT-11)liposomes and develop a method for the determination of its entrapment efficiency.Methods CPT-11 was encapsulated in the liposomes by ammonium ethylenediaminetetraacetate(NH4EDTA)gradient method.Free CPT-11 and liposomes was separated by cation exchange resin.UV-visible spectrophotometry was applied to determine the entrapment efficiency.Results 1.0-2.4 g·L-1 CPT-11 was completely absorbed by cation exchange resin,while blank liposomes was not absorbed.The recovery rate of liposomes was 99.73%.In the conditions of the UV-visible spectrophotometry method,blank adjuvant could not interfere with determination of CPT-11 at 372 nm wave-length.The standard curve was linear over the range of 2.5-45.0 mg·L-1 with the coefficient of 0.999 9.The precision and recovery of the method accorded with the requirement.The entrapment efficiency of CPT-11 liposomes by NH4EDTA gradient method was 95.4%.Conclusions The NH4EDTA gradient method is suitable for preparing CPT-11 liposomes.The method established in this study is simple,rapid and accurate for the determination of the entrapment efficiency of CPT-11 liposomes.