苯磺酸左旋氨氯地平血药浓度的LC-MS/MS法测定及其人体内手性转化可能性考察

目的 建立LC-MS/MS法测定人血浆中左旋氨氯地平血药浓度并进行体内手性转化可能性考察。 方法 以氯氮为内标, 采用CHIRAL-AGP柱(150.0 mm×4.0 mm, 5 μm)对氨氯地平消旋体进行分离手性对映体, 流动相为10 mmol/L乙酸铵缓冲液(pH 4.38)-异丙醇(982, V/V)；选择固相萃取法提取10例健康男性受试者单次口服苯磺酸左旋氨氯地平片2.5 mg 后的血浆样品, 大气压化学电离源(APCI)结合正离子MRM扫描分析测定人体内S-(-)-氨氯地平浓度, 其中氨氯地平和内标离子对分别是m/z 409.0→237.9和m/z 300.0→282.0。 结果 S-(-)-/R-(+)-氨氯地平对映体血药浓度在0.103 1~20.62 μg/L范围内线性关系良好(r=0.999 8, r=0.999 7), 绝对回收率大于70.0%, 相对回收率均在85.0%~115.0% 范围内, 日内和日间RSD均小于15.0%。10例健康男性受试者单剂量口服苯磺酸左旋氨氯地平片2.5 mg后体内不同时间点血浆样品均未检测到R-(+)-氨氯地平对映体, S-(-)-氨氯地平在健康男性受试者体内的药代动力学参数t1/2为(42.77±8.08) h, Cmax为(3.06±0.51) μg/L, tmax为(6.3±1.0) h, MRT为(69.25±8.04) h, AUC0-144为(176.20±31.89) h·μg·L-1, AUC0-∞为(197.92±37.54) h·μg·L-1。 结论 本方法 选择性强, 灵敏度高, 无杂质干扰, 精密度好, 成功地应用于苯磺酸左旋氨氯地平人体药代动力学分析, 并证实S-(-)-氨氯地平对映体在健康男性受试者体内未发现其手性转化。

Determination of levamlodipine concentration by LC-MS/MS and its chiral transformation potential in human plasma

Objective To determine S-(-)-amlodipine level in human plasma by LC-MS/MS method,and to investigate its chiral transformation potential in healthy male volunteers.Methods The separation of amlodipine was performed by CHIRAL-AGP analytical column(150.0 mm×4.0 mm,5 μm) with 10 mmol/L acetate buffer(pH 4.38)-2-propanol(982,V/V) as the mobile phase and chlordiazepoxide as the internal standard.The plasma S-(-)-amlodipine was extracted with solid phase extraction in ten healthy male volunteers at different time points after oral test(2.5 mg).Atmospheric-pressure chemical ionization(APCI) and multiple reaction monitoring(MRM) were used with positive ion scans,and the mass transition pairs of m/z 409.0→237.9 and m/z 300.0→282.0 were used to detect amlodipine and internal standard,respectively.Results The linear calibration curve of each enantiomer of amlodipine showed excellent correlation over the range of 0.1031 μg/L(20.62 μg/L(r=0.999 8,r=0.999 7).The absolute recovery was more than 70.0%,the relative recoveries were 85.0%-115.0%,and intra-run and inter-run relative standard deviation(RSD) were less than 15.0%.No R-(-)-amlodipine was detected in the plasma of ten healthy male volunteers at different time points after single oral test.The main pharmacokinetic parameters of S-(-)-amlodipine in healthy male volunteers were as follows:t1/2 was(42.77±8.08) h,Cmax was(3.06±0.51) μg/L,tmax was(6.3±1.0) h,MRT was(69.25±8.04) h,AUC0-144 was(176.20±31.89) h·μg·L-1,and AUC0-∞ was(197.92±37.54) h·μg·L-1.Conclusion The present method is highly selective,sensitive,accurate and with no endogenous interference for pharmacokinetic study.R-(+)-amlodipine is not found in the plasma,indicating that there is no chiral transformation in healthy male volunteers.