UPLC-MS/MS快速测定大鼠血浆中的氯沙坦及其代谢产物

目的 建立快速测定大鼠体内氯沙坦及其代谢产物（E-3174）浓度的UPLC-MS/MS方法。方法 Waters XEVO TQD三重四级杆液质联用仪， 色谱柱为ACQUITY UPLC BEH C18柱（100 mm ×2.1 mm，1.7 μm）；流动相为乙腈-水（含0.1%甲酸和0.5%氨水）（60∶40），流速为0.2 mL·min^-1，柱温30 ℃，内标为地西泮；质谱条件：电喷雾离子化源（ESI），正离子检测模式；加入200 μL乙腈沉淀蛋白，13 000 r·min^-1离心10 min转移至1.5 mL EP管中取2 μL上样。结果 E-3174的保留时间为1.54 min，线性范围为6.25～800 ng·mL^-1（r=0.999 8），最低定量限为0.5 ng·mL^-1，回收率为96.6%～98.37%；氯沙坦的保留时间为1.38 min，线性范围为12.5～1 600 ng·mL^-1（r=0.999 6），最低定量限为1.0 ng·mL^-1，回收率为98.4%～100.6%。两者的日内、日间RSD均〈5%，孵育体系中的其他内源性物质不干扰测定。结论 该方法操作简便，重复性好，适于快速测定大鼠体内氯沙坦及其代谢产物浓度。

Rapid Determination of Losartan and Its Metabolite by UPLC-MS/MS

OBJECTIVE To construct an ultra performance liquid chromatography-tandem quadru- pole mass spectrometry method to determine the concentration of losartan and its metabolite （E-3174） in rat plasma. METHODS An ACQUITY UPLC BEH C18（100 mm×2.1 mm, 1.7 μm） column was used as the stationary phase at 30 ℃ on Waters XEVO TQD. The mobile phase was consisted of acetonitrile and water （ containing 0.01% formic acid and 0.05% ammonia water） （60∶40）. The flow rate was 0.2 mL·min^-1. Plasmas were precipitated with 200 μL acetonitrile and centrifugated at 13 000 r·min-1 for 10 min. RESULTS The retention time of E-3174 was 1.54 min. Excellent linear calibration curves of E-3174 was obtained in the concentration range of 12.5-1 600 ng·mL^-1（r=0.999 6）. The lower limit of quantification of E-3174 was 0.5 ng·mL^-1 while the average recovery was 96.6%-98.37%. The retention time of losartan was 1.38 min and the linear calibration curves of losartan was obtained in the concentration range of 12.5-1600 ng·mL^-1（r=0.999 6）. The average recovery was 98.4%-100.6%. The intra and inter day relative standard deviations were〈5%. There were no endogenous substances existing in the incubation system which interfered with the determination of the analyses of interest. CONCLUSION The method is accurate, simple and rapid, and suitable for the determination of losartan and its metabolite （E-3174） in rat plasma.