LC-MS/MS测定人血浆中辛伐他汀及其活性代谢物的含量

LC-MS/MS determination of simvastatin and its active metabolite in human plasma

目的:建立人血浆中辛伐他汀及其活性代谢物辛伐他汀酸的LC-MS/MS测定方法。方法:血浆样本在酸性条件下经甲基叔丁基醚液液萃取后,以2.5 mmol.L-1醋酸铵(含0.1%甲酸)-乙腈(25∶75)为流动相,采用Inertsil ODS-3(2.1 mm×150 mm,5μm)色谱柱分离。使用电喷雾离子源以多反应监测(MRM)方式分别进行正负离子监测。辛伐他汀选用洛伐他汀作为内标,在正离子模式下检测;代谢物辛伐他汀酸选用洛伐他汀酸作为内标,在负离子模式下监测。结果:测定血浆中辛伐他汀及其代谢物辛伐他汀酸的线性范围均为0.1～20.0μg.L-1;方法回收率分别为86.1%～100.5%,91.5%～104.4%;日内精密度分别为3.2%～4.7%和4.5%～6.9%,日间精密度分别为3.6%～9.8%和2.3%～10.5%。结论:该方法简便快速、灵敏度高、重复性好,可准确的定量人血浆辛伐他汀及代谢物辛伐他汀酸的浓度,适用于辛伐他汀药代动力学研究。

Objective ： To establish an LC - MS/MS method for the determination of simvastatin and its active me- tabolite （simvastatin acid）in human plasma. Methods：The acidified sample was extracted by MTBE, then separated on an Inertsil ODS -3 （2. 1 mm 150 mm,5 μm）column with 2.5 mmol . L-1 ammonium acetate（containing 0. 1% formic acid） -acetonitrile（25：75）as mobile phase. Electrospray ionization source（ESI） was applied and op- erated in multiple reactions monitoring（MRM） mode. Simvastatin was detected in positive ion mode with lovastatin as internal standard, and its active metabolite was determined in negative ion mode with lovastatin acid as internal standard. Results：The calibration curves of simvastatin and its active metabolite were linear in the range of 0. 1 - 20. 0 μg. L-1. The method recoveries were 86. 1% - 100. 5% % and 91.5% - 104. 4% ,respectively. The intra - day precisions were 3.2% -4. 7% and 4. 5% -6. 9%, respectively;the inter - day precisions were 3.6% -9. 8% and 2. 3% -10. 5%, respectively. Conclusions ：The method is simple ,rapid, sensitive and reproducibility for the determi- nation of simvastatin and its metabolite in human plasma. It is suitable for the pharmacokinetic study of simvastatin.