Zhang Shuang-Qing, Thorsheim Helen R, Penugonda Suman, Pillai Venkateswaran C, Smith Quentin R, Mehvar Reza
Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, 1300 Coulter, Amarillo, TX 79106, USA.
J Chromatogr B Analyt Technol Biomed Life Sci. 2009 Apr 1;877(10):927-32. doi: 10.1016/j.jchromb.2009.02.028. Epub 2009 Feb 21.
A specific and sensitive liquid chromatography (LC)-tandem mass spectrometric method for quantitative determination of methylprednisolone (MP) in rat plasma and liver was developed and validated using triamcinolone acetonide as an internal standard. Liquid-liquid extraction using tert-butyl methyl ether was used to extract the drug and the internal standard from plasma and liver. The separation of MP was performed on a C(18) column with a mobile phase of acetonitrile:0.5% formic acid aqueous solution (85:15, v/v) over 4min. The assay was based on the selected reaction monitoring transitions at m/z 375-->161 for MP in plasma, 375-->357 for MP in liver, and 435-->415 for internal standard in both plasma and liver. The lower limit of quantification was 20ng/mL based on 100microL of plasma or liver homogenate. Intra- and inter-day assay variations were <or=15%, and the accuracy values were between 85.8% and 118%. The extraction recoveries ranged from 76.8% to 79.2% for plasma and 76.8-80.8% for liver across the calibration curve range. The method was successfully applied to the measurement of low concentrations of regenerated MP in plasma and liver after intravenous administration of a single dose (5mg/kg) of a liver-targeted dextran prodrug of MP to rats.
建立了一种特异性强、灵敏度高的液相色谱（LC）-串联质谱法，以曲安奈德为内标，用于定量测定大鼠血浆和肝脏中的甲泼尼龙（MP）。采用叔丁基甲醚液-液萃取法从血浆和肝脏中提取药物和内标。MP在C(18)柱上进行分离，流动相为乙腈:0.5%甲酸水溶液（85:15，v/v），洗脱时间为4分钟。该测定基于血浆中MP的m/z 375→161、肝脏中MP的m/z 375→357以及血浆和肝脏中内标的m/z 435→415的选择反应监测跃迁。基于100μL血浆或肝脏匀浆，定量下限为20ng/mL。日内和日间测定变异<或=15%，准确度值在85.8%至118%之间。在校准曲线范围内，血浆的萃取回收率为76.8%至79.2%，肝脏的萃取回收率为76.8%至80.8%。该方法成功应用于大鼠静脉注射单剂量（5mg/kg）MP的肝靶向葡聚糖前药后血浆和肝脏中低浓度再生MP的测定。
