LC-MS/MS法测定人血浆中雷洛昔芬及其临床药代动力学研究

Determination of Raloxifene in Human Plasma by Liquid Chromatography-Mass Spectrometry and Its pharmacokinetics

目的:建立人血浆中雷洛昔芬(Raloxifene,RAL)的LC-MS/MS测定方法,研究口服RAL60 mg/d后RAL及其葡萄糖醛酸代谢产物的体内药代动力学过程。方法:绝经后女性志愿者单剂量口服雷洛昔芬60 mg/d,在0、0.5、1、2、4、6、8、24、48、72 h时间点采集血液样品,分离血浆后,经乙腈沉淀蛋白后采用液-液萃取法提取,进行LC-MS/MS分析。RAL及其代谢产物雷洛昔芬-6葡萄糖醛酸苷(M1)、雷洛昔芬-4’葡萄糖醛酸苷(M2)的多重反应监测的离子对分别为m/z 474.2/112.2、650.3/474.2和650.3/474.2。结果:RAL及其代谢物M1、M2的定量下限分别为0.195、0.975和3.9 nmol/L,提取回收率为77.14%~83.64%。人体中RAL及其代谢物M1、M2的药代动力学参数:RAL、M1和M2的Cmax分别为(0.45±0.043)、(92.22±12.84)、(466.71±113.50) nmol/L;AUC0~t分别为(19.55±0.65)、(2 133.25±326.91)、(7 344.45±819.18)μmol h/L;T1/2分别为(69.48±25.26)、(100.10±29.80)、(29.65±0.92) h。结论:建立的LC-MS/MS分析方法准确灵敏,适用于RAL的临床药代动力学研究。RAL吸收后被快速代谢成了M1、M2,其体内药代动力学特点是半衰期长。建议RAL的临床药代动力学研究需同时检测其葡萄糖醛酸化代谢产物。

Objective To establish a LC-MS/MS method for the determination of raloxifene(RAL) in human plasma and investigate the pharmacokinetics of RAL and its glucuronide metabolites after oral administration of RAL 60 mg/day. Methods The blood samples were collected at 0, 0.5, 1, 2, 4, 6, 8, 24, 48 and 72 h after a single oral dose of raloxifene in postmenopausal female volunteers. After plasma separation, the protein was precipitated by acetonitrile and extracted by liquid-liquid extraction method for LC-MS/MS analysis. The monitored ion pairs for raloxifene and its metabolites raloxifene-6 glucuronide(M1) and raloxifene-4’glucuronide(M2) were m/z 474.2/112.2, 650.3/474.2 and 650.3/474.2 in multiple reaction monitor mode for UPLC-MS/MS analysis,respectively.Results The quantitive limits of RAL and its metabolites M1 and M2 were 0.195, 0.975 and 3.9 nmol/L, respectively. The extraction recovery was from 77.14% to 83.64%. The pharmacokinetic parameters of RAL, M1 and M2 were as follows: Cmax of RAL, M1 and M2 were(0.45±0.043),(92.22±12.84),(466.71±113.50) nmol/L, respectively;AUC0~t were(19.55±0.65),(2 133.25±326.91),(7 344.45±819.18) μmol h/L, respectively;T1/2 were(69.48±25.26),(100.10±29.80),(29.65±0.92) h, respectively. Conclusion The established LC-MS/MS analysis method is accurate and sensitive, which is suitable for the clinical pharmacokinetic study of RAL. Raloxifene was rapidly metabolized into M1 and M2 after absorption, and its pharmacokinetics was characterized by long half-life. It is suggested that the glucuronization metabolites of RAL should be detected simultaneously in clinical pharmacokinetic study.