目的 建立LC-MS/MS方法测定芫花素在大鼠体内的血药浓度，并研究其药物动力学。方法 大鼠灌胃芫花提取物，眼眶采血，离心，以蛋白沉淀法处理血浆样品，芒柄花素为内标，电喷雾离子化，多反应检测方式进行负离子检测，检测离子质荷比(m/z)分别为283.2/267.9，267.0/251.9。使用Phenomenex Gemini 110 C18色谱柱(50 mm×2.0 mm，5 μL)；以甲醇- 0.1 %甲酸水(85∶15)为流动相，等度洗脱；柱温:40 ℃；流速:0.3 mL·min-1。结果 大鼠灌胃芫花提取物后的药-时曲线符合二房室模型，芫花素血药浓度在5～1000 ng·mL-1范围内线性关系良好(r2=0.998)，最低检测限(LOQ)为0.5 ng·mL-1，日内及日间精密度(RSD)为2.42 %～10.71 %，日内及日间准确度为95.67 %～112.15 %，血浆中无内源性基质干扰，稳定性良好。结论 本研究所建立的方法简便、灵敏、重复性好、分析速度快，可用于血浆样品中芫花素的血药浓度测定和大鼠体内药物动力学研究。

Objective To develop a simple，sensitive and rapid method for determining the concentrations of genkwanin in rat plasma by using liquid chromatography coupled to tandem mass spectrometry(LC-MS/MS) and to study the pharmacokinetics of genkwanin. Methods Rats were given Flos Genkwa extract and then the rat blood was sampled from the eye sockets for the preparation of plasma by protein precipitation method. Formononetin was used for the internal standard，and the detection of genkwanin was performed by negative ion electrospray ionization(ESI) in multiple reactions monitoring(MRM) mode with m/z being 283.2/267.9. The method included a chromatographic run for 3 min by using a Gemini C18 column(50 mm × 2.0 mm，5 μm，Phenomenex，USA)，and the mobile phase consisted of 0.1 ％ formic acid water solution(solvent C) and methanol(solvent B) as mobile phase by isocratic elution. The flow rate was set at 0.3 mL·min-1 with split ratio of 15 ∶ 85. The column temperature was maintained at 40 ℃ using a column heater. Results The calibration curve was linear in the genkwanin concentration range of 5～1000 ng·mL-1 with a correlation coefficient(r2=0.998) of 0.996 or better and the lowest limit of quantification was 0.5 ng·mL-1. The intra- and inter-day assay precision ranged from 2.42 % ～ 10.71 %，and intra- and inter-day assay accuracy was between 95.67 % ～ 112.15 %. The method had good stability，without any endogenous interference. Conclusion The data indicate that our LC-MS/MS assay is an effective method for the pharmacokinetic study of genkwanin in rat plasma.

R285.5

广东省“211工程”三期重点学科建设项目“药物警戒系统中的中药安全性再评价研究”专项基金(粤发改社(2009)972号)。