高效液相色谱-质谱法测定人血浆中甘草次酸浓度及人体药代动力学研究

目的建立人血浆中甘草次酸的高效液相色谱-质谱(LC-MS)测定法，并用于健康志愿者的药代动力学研究。方法20例健康志愿者一次口服甘草酸二铵胶囊150mg，采集肘静脉血并分离血浆，血样经乙酸乙酯提取后，以熊果酸为内标，进行LC-MS分析。色谱柱：Venusil XBP-C18柱(5μm, ID4.6×150mm)，流动相：甲醇(5mmol/L乙酸铵)-水(85∶15，V/V)，梯度洗脱；流速：0.8mL/min，柱温25℃，进样10μL。甘草次酸和内标熊果酸的检测离子和裂解电压分别为m/z 469.5、m/z 455.6和200V、100V。根据不同时间甘草次酸血浓度计算其药代动力学参数。结果在0.5～200ng/mL范围内，甘草次酸与内标的峰面积比值与浓度线性关系良好，相关系数为0.9974，定量限为0.5ng/mL，提取回收率为76.0%～80.0%,日内、日间RSD均小于12%。甘草次酸口服给药Cmax为(95.57±43.06)ng/mL，Tmax为(10.95±1.32)h。结论高效液相色谱-质谱测定法灵敏、准确、简便，适用于血浆甘草次酸的浓度测定及其人体药代动力学研究。

HPLC-MS determination and pharmacokinetic study of glycyrrhetic acid in human plasma

To develop a LC-MS method for the determination of glycyrrhetic acid in human plasma and for evaluation of its pharmacokinetic characteristics．Methods Glycyrrhetic acid in plasma was extracted with ethyl acetate， separated on a C18 column with a mobile phase of methanol(5mmol/L ammonium acetate) water(85∶15，V/V) and analyzed by the LC MS method with ursolic acid(UA) as the internal standard．The target ions were m/z 469.5 for glycyrrhetic acid and m/z 455.6 for internal standard. The fragmentor voltages were 200V for glycyrrhetic acid and 100V for the internal standard. ResultsThe calibration curve was linear over the range of 0.5 to 200ng/mL (r=0.9974). The quantitative limit for glycyrrhetic acid in plasma was 0.5ng/mL, the recovery rate was 76.0% to 80.0%, and the inter day and intra day derivations (RSD) were less than 12%. The Cmax and Tmax of glycyrrhetic acid were (95.57±43.06)ng/mL and (10.95±1.32)h after oral administration. Conclusion The assay proved to be sensitive，accurate and convenient and can be applied in the determination of glycyrrhetic acid in human plasma and its pharmacokinetic study．