阳离子树脂吸附分离-HPLC测定乳酸司帕沙星脂质体的包封率

 目的建立乳酸司帕沙星脂质体包封率的测定方法、方法采用HPLC测定药物含量,用Hypersil ODS2柱(4.6 mm×250mm,5μm),0.2mol·L^-1醋酸铵溶液(用冰醋酸调pH至3.5)-乙晴(70:30)为流动相,流速为1.0mL·min^-1,检测波长为298nm;采用5mL阳离子树脂柱分离脂质体中的游离药物,加样量0.2mL,用13mL去离子水洗脱,测定包封率。结果乳酸司帕沙星在4.2～50.4mg·L^-1内与峰面积线性关系良好(r=1.000),精密度RSD小于1.3%,回收率为99.96%～102.1%(RSD为0.9%～1.3%,n=3);5mL阳离子树脂柱对游离药物的平均吸附率大于96.4%,且对脂质体的洗脱率大于97.4%,可以将脂质体与游离药物分离。结论采用阳离子树脂吸附分离-HPLC测定乳酸司帕沙星脂质体中药物包封率简便快速,结果较可靠。

Determination of Entrapment Efficiency in Sparfloxacin Lactate Liposomes by Cation Exchange Resin- HPLC

OBJECTIVE To establish cation exchange resin-HPLC method for the determination of entrapment efficiency in sparfloxacin lactate liposomes.METHODS The content of sparfloxacin lactate was determined by HPLC with Hypersil ODS2 column (4.6 mm×250 mm,5μm).The mobile phase consisted of 0.2 mol·L^-1ammonium acetate solution(adjusted to pH 3.5 with acetic acid)-acetnnitrile(70:30),at a flow-rate of 1.0 mL·min^-1.The UV detection was set at 298 nm.The 5 mL column with cation exchange resin was adopted to separate free sparfloxcain lactate from liposomes dispersions.The 0.2 mL sample was added and washed through resin column with 13 mL deionized water.RESULTS The linear-calibration curves were obtained in the concentration range of 4.2-50.4 mg·L^-1(r=1.000).The precision(RSD)was below 1.3%.The recoveries of sparfloxacin lactate with blank liposomes were 99.96%-102.1%(n=3).The free sparfloxaein lactate was well separated from liposomes dispersions and was adsorbed up to 96.4% by cation exchange resin,and the average recovery of liposomes were more than 97.4%.CONCLUSION This method is technically simple,rapid and efficient and is proved to be suitable for separating and determining entrapment efficiency of cationic drug liposomes.