液相色谱-串联质谱法同时测定人血浆中氯沙坦及其活性代谢物氯沙坦酸的浓度

Simultaneous determination of losartan and its active metabolite losartan acid in healthy volunteers by LC-MS/MS method

目的建立测定人血浆中氯沙坦及其活性代谢物氯沙坦酸的液相色谱一串联质谱（LC—MS／MS）法，并将其应用于健康受试者体内的药动学研究。方法血浆样品经乙醚提取后。采用ThermoC柱（100mm×2．1mm，5μm）进行分离，流动相为甲醇：5mmol·L-醋酸铵水溶液-甲酸=90：10：0．005（V／V／V），流速为0．2mL·min～；选用电喷雾（ESI）离子源，在正离子电离模式下，采用选择反应监测（SRM）的质谱扫描方式，用于定量分析的离子反应分别为m／z423—，m／z207（氯沙坦）、m／z437一m／z235（氯沙坦酸）和m／z285-，m／z193（地西泮，内标）。22名男性健康受试者口服50mg氯沙坦钾片后，测定人血浆中氯沙坦和氯沙坦酸的浓度，并计算主要药动学参数。结果人血浆中氯沙坦和氯沙坦酸分别在1．0～500Ixg·L-1，5．0～2000斗g·L-1范围内线性关系良好，定量下限分别达到1．0μg·L。和5．0μg·L-1；日内、日间精密度均小于15％。人血浆中氯沙坦及其活性代谢物氯沙坦酸在22名健康男性受试者体内的主要药动学参数如下：tl，2分别为（2．30±0．63）和（3．30±0．83）h，p-分别为（188．7±108．3）和（274．6±107．4）μg·L～，分别为（1．03±0．77）和（3．14-I-0．94）h，AUC0。分别为（305．4±116．5）和（1451．3±661．0）Ixg·h·L～，AUCo一。分别为（312．1±118．8）和（1611．6±670．9）μg·h·L～。结论本实验建立的LC—MS／MS法准确、灵敏、快速，适用于同时测定人血浆中氯沙坦及其活性代谢物氯沙坦酸的浓度，并成功应用于人体内的药动学研究。

AIM To establish a simple, rapid and sensitive liquid chromatography- tandem mass spectrometry （LC-MS/MS） method for measuring plasma losartan and its active metabolite losartan acid, and tostudy the pharmacokinetics of losartan in healthy humans. METHODS The plasma samples were extracted by ethyl ether, and separated using Thermo C18 （ 100 mm x 2.1 mm, 5 μm） with a mobile phase of methanol/ ammonium acetate （5 mmol.L-t） /formic acid （ 90 ： 10 ： 0.005, V/V/V） at a flow rate of 0.2 mL.min i. Mass spectrometric detection was achieved by mass spectrometer equipped with an electrospray source interface operating in positive ionization mode. Precursor-product ion transitions at m/z 423 ~ m/z 207 （losartan）, m/z 437 --~ m/z 235 （losartan acid） and m/z 285 -~ m/z 193 （diapazem , internal standard） were quantified using selected reaction monitoring system. RESULTS This measurement was linear over the range of 1.0 - 500 μgL-I, 5.0 - 2 000 μg L-t for losartan and losartan acid, respectively. The RSD values of both intra-and inter-day precision were less than 15%. The main pharmacokinetic parameters of losartan and its active metabolite losartan acid in healthy humans were as follows： t~ were （2.30 _＋ 0.63） and （3.30 _＋ 0.83） h, p,,~, were （188.7 ＋ 108.3） and （274.6 _＋ 107.4） Ixg＇L-l, t,~, were （1.03 _＋ 0.77） and （3.14 ＋_ 0.94） h, AUCo_~ were （305.4 _＋ 116.5） and （1 451.3 _＋ 661.0） Ixg＇h＇L-I, AUC0-1 were （312.1 ＋_ 118.8 and （1 611.6 _＋ 670.9） Ixg,h-L-l, respectively. CONCLUSION The LC- MS/MS method was accurate, sensitive and quick, and successfully applied to the pharmacokinetic study of losartan in human plasma.