液-质联用法测定大鼠血浆中ZTW-41浓度

目的:建立快速、灵敏、准确的LC-MS/MS法测定大鼠血浆中ZTW-41的浓度,并将该方法应用于ZTW-41的药动学研究。方法:以卡马西平为内标,血浆样品用甲醇沉淀蛋白后,通过ZORBAX Esplise XDB-C18色谱柱(4.6 mm×100 mm,3.5-Micron)进行分离,选择75%甲醇溶液(含5 mmol·L-1甲酸铵和0.1%甲酸)-甲醇溶液(含5 mmol·L-1甲酸铵和0.1%甲酸)作为流动相进行等度洗脱,流速为0.5 mL·min-1。通过ESI,以多反应监测模式(MRM)进行正离子检测,ZTW-41和卡马西平的MRM离子对分别为m/z 540.0→168.2和m/z 237.0→194.2;大鼠尾静脉给予ZTW-41前和给药后不同时间点采集血浆,血浆样品前处理后进行LC-MS/MS检测分析。结果:大鼠血浆中ZTW-41在10~3000 ng·mL-1浓度范围内具有良好的线性关系,R2≥0.99;定量下限和各浓度质控样品批间、批内精密度(RSD%)在5.82%以内,准确度(RE%)在-0.81%~4.87%之间。大鼠尾静脉给予20 mg·kg-1的ZTW-41后,Cmax为(244.78±46.67)ng·mL-1,t1/2为(21.17±2.08)h。结论:本研究建立的LC-MS/MS定量分析方法可快速、灵敏、准确地测定大鼠血浆中ZTW-41的浓度,并成功应用于ZTW-41的药动学研究。

Quantification of ZTW-41 in rat plasma by LC-MS/MS

OBJECTIVE To establish a rapid, sensitive and accurate LC-MS/MS method for the determination of ZTW-41 in rat plasma, and to apply this method to the pharmacokinetic study of ZTW-41.METHODS ZTW-41 in rat plasma was extracted by protein precipitation using methanol and carbamazepine was used as internal standard. The analytes were separated on a ZORBAX Esplise XDB-C₁₈ column (4.6 mm×100 mm, 3.5-Micron). 75% methanol solution (containing 5 mmol·L^-1 ammonium formate and 0.1% formic acid)-methanol solution (containing 5 mmol·L^-1 ammonium formate and 0.1% formic acid) was employed as a mobile phase with a flow rate of 0.5 mL·min^-1. Mass detection was carried out using an electrospray ionization (ESI) source operating in positive mode. ZTW-41 and carbamazepine were analyzed by multiple reaction monitoring (MRM) and the ion transitions were m/z 540.0→168.2 and m/z 237.0→194.2, respectively. Blood samples were collected into heparinized centrifuge tubes by the postorbital venous plexus vein from each rat before and different time points after intravenous administration of ZTW-41. Plasma samples were pretreated and analyzed by LC-MS/MS.RESULTS ZTW-41 was determined over a linear calibration curve ranging from 10 to 3 000 ng·mL^-1, (R² ≥ 0.99). The inter- and intra-assay precision (RSD%) were less than 5.82%, and the accuracy (RE%) was within the range of -0.81%-4.87%. After intravenous administration of ZTW-41 at doses of 20 mg·kg^-1 to rats, the C_max was (244.78±46.67) ng·mL^-1; while the t_1/2 was (21.17±2.08) h.CONCLUSION The LC-MS/MS quantitative analysis method established in this study can rapidly, sensitively and accurately determine the concentration of ZTW-41 in rat plasma and was successfully applied to the pharmacokinetic study of ZTW-41.