LC—MS法测定人血浆中米氮平浓度及应用

研究了液相质谱联用仪（LC—MS）测定人血浆中米氮平浓度的方法。在碱性条件下用乙酸乙酯提取，以盐酸苯海拉明为内标。采用XDB—C18反相柱（5μ），质谱检测器采用AP—ESI，正离子模式，采集方式为SIM。流动相为甲醇-水（含0．1％醋酸和0．2％醋酸铵）（70：30，v／V）。在上述条件下米氮平在0．4～150ng／mL范围内线性关系良好，提取回收率大于75％，重现性相对标准差（RSD）均小于10％，检测限为0．4ng／mL。结果表明，该法方便、准确、灵敏，适用于米氮平片剂的药代动力学研究，也可以用于临床测定米氮平血浆药物浓度。

LC-MS Based Determination of Mirtazapine in Human Plasma

We propose a LC-MS approach to determine Mirtazapine concentration in human plasma with diphenhydramine hydrochloride as an internal standard. Its conditions are reverse-phase Inertsil C18 column（5μ）, mobile phase methanol-water（0.1% acetic acid and 0.2% ammonium acetate） （70：30, v/v）, flow rate 1.0 mE/rain,plasma extraction by ethyl acetate in basic condition and detection with an electrospray ionization mass spectrometer in positive ion and selected-ion surveillance mode. We completely separated Mirtazapine and internal standard in these conditions. Results show that Mirtazapine has a good linear relationship between 0.4 and 150 ng/mL. RSD is less than 10%. Average recovery rate is more than 75% . Plasma concentration of LQD is 0.4 ng/ml. The approach is therefore convenient, rapid, accurate and suitable for determination of Mirtazapine in human plasma and pharmacokinetic research.