LC—ESI—MS／MS法快速测定人血浆中环丙沙星的浓度

建立测定人血浆中环丙沙星浓度的高效液相色谱串联质谱电喷雾法（LC-ESI-S／MS）。方法以Agilent ZORBAX C18反相柱（Agilent ZORBAX TC-C18 column，4．6mm×150mm，5μm）为色谱柱，流动相为乙腈（含1％甲酸）-0．02mol·L^-1甲酸铵水溶液：90：10（V：V），流速为0．8mL·min^-1，柱温：25℃，采用乙腈沉淀簧白法。样品经电喷雾离子源正离子化后，通过三重四级杆串联质谱仪，采用选择反应监测（SRM）对环丙沙星（rdz332．2—314．2）和洛美沙星（m／z352．2→265．1）进行测定。并用此法测定20例健康受试者单次口服500mg后的血药浓度。结果环丙沙星的高（2500μg·L^-1）、中（250μg·L^-1）、低（10μg·L^-1）3个浓度的平均回收率分别为101．22％、102．31％和93．19％，日内（n=5）、日间（n=3）RSD均小于15％；分析方法的最低定量限为5μg·L^-1。线性范围为：5～5000μg·L^-1，回归方程为：F=30692．75ρ-0．0014，r=0．997（n=8）．权重为1／ρ^2。结论该方法灵敏、准确、简单、快速．可用于临床血浓监测和药动学研究。

Rapid determination of ciprofloxacin in plasma by LC-ESI-MS/MS

OBJECTIVE To set up a LC-ESI-MS/MS method for ciprofloxacin assay in plasma.METHODS Ciprofloxacin was extracted with acetonitrile. The residues were analyzed with a LC-ESI-MS/MS system （Agilent ZORBAX TC-C18,4.6 mm × 150 mm, 5 μm） with the mobile phase consisted of acetonitrile （1% formic acid） ： 0.02 mol·L^-1 ammonium formate= 90：10（V： V）. Agilent 6410 triple quad mass spectrometer system equipped with an electrospray ionization ion-trap source was used as the detector and operated in the positive ion mode. Selected reaction monitoring（SRM） using the precursor to produce ion combinations of m/z 332.2→314.2 and m/z352.2→265.1 was performed to detect ciprofloxacin and the internal standard, respectively. The method was used to evaluate clinical application on 20 heathly volunteers after oral doses of the ciproftoxacin hydrochloride tablets. RESULTS The average recoveries for ciprofloxacin were 101.22 %, 102.31% and 93.19 %, respectively.The within-day （n= 5） and between-day （n = 3） precision of variation was less than 15% .The calibration curves for ciprofloxacin had good linearity, r = 0. 997 （n = 8）, over the range of 5 -- 5000μg·L^-1. The limits of quantitation for ciprofloxacin was 0.5 μg·L^-1 .CONCLUSION The method provides a sensitive, accurate, precise and reliable analytical procedure for clinical monitoring of ciprofloxacin plasma and its phamacokinetic studies.