限进液相色谱法同时测定人血浆中拓扑替康内酯型和羧酸型的浓度

Simultaneous determination of the carboxylate and lactone forms of topotecan in human serum by restricted-access media HPLC

目的:使用限进填料液相色谱法,建立一个直接进样同时测定人血浆中拓扑替康内酯型和羧酸型浓度的方法。方法:限进填料色谱柱(150 mm×4.6 mm,5μm);柱温:40℃;流动相:甲醇-0.05 mol/L磷酸盐缓冲液(含1%三乙胺,pH6.6)=13:87(v/v);流速:1ml/min;进样量:20μl;荧光检测λex390nm/λem520nm。结果:平均回收率为94.50%,校正曲线线性范围为15~1000ng/ml。日内和日间RSD均<7%。由分析结果推得的动力学方程显示,37℃时在人血浆中拓扑替康内酯型和羧酸型为一级动力学过程,由此可进一步外推出采样时刻拓扑替康内酯型和羧酸型各自的浓度。结论:本法准确、快速,适用于拓扑替康两种结构的血药浓度同时测定及其药动学研究。

Objective:To develop a simple restricted-access media(RAM)HPLC method for simultaneous determination of lactone and carboxylate forms of topotecan(TPT)in human serum.Methods:Using a RAM analytical column,serum samples were directly injected into the HPLC system.The eluted peaks of two forms of TPT were monitored with a fluorescence detector.Results:The separation was completed in18 min.The linear range was 15-1000ng/ml,intra-day and inter-day variations were less than 7%.The kinetic equation was constructed according to the analytical results.The equation showed that the course of TPT lactone form converting to carboxylate form in human serum at 37 degree followed a firstorder kinetics.Concentration of each form at the moment of sampling was calculated by extrapolation.Conclusion:This method will be useful in clinical pharmacokinetic and pharmacodynamic studies of TPT and its derivatives.