反相高效液相色谱法测定人血浆中甲哌卡因的浓度

目的:建立反相高效液相色谱紫外法测定人血浆中甲哌卡因浓度。方法:采用Diamonsil ODS C₁₈分析柱（150 mm×4.6 mm,5μm）,柱温为室温,流动相为甲醇-乙腈-0.03 mol·L^-1KH₂PO₄缓冲液（H₃PO₄调pH为5.3）（50:50:250）,流速:1.0ml·min^-1;0.5 ml血浆样品经固相萃取方法处理后,洗脱液在50℃条件下空气吹干,残渣用流动相溶解进样,紫外检测器检测,检测波长为210 nm。结果:标准曲线在20～4 000 ng·ml^-1范围内线性良好,最低定量限为20 ng·ml^-1,甲哌卡因及内标的保留时间分别为7.5 min和19.4 min,日内和日间RSD均<14.0%,方法提取回收率分别在103.5%～109.2%。结论:本法具有简便、灵敏、准确等优点,成功用于经硬膜外给予200 mg盐酸甲哌卡因患者血浆液中甲哌卡因浓度测定及药动学研究。

Determination of Mepivacaine in Human Plasma by RP-HPLC

Objective： To establish a RP-HPLC method with ultraviolet detection for the determination of mepivacaine in human plasma. Method： Diamonsil ODS Cls analysis column （150 mm ×4.6mm,5μm） was used. An aliquot of 0. 5ml human plasma was treated by solid-phase extraction （SPE）. After evaporation of the organic layer,the residue was dissolved in 100μl mobile phase and 50 μl was injected into the column. The mobile phase, consisted of methanol-acetonitrile-0.03 mol·L^-1 potassium dihydrogen phosphate （pH was adjusted to 5.3 by NaOH） （ 10： 10： 50） ,was delivered at rate of 1.0 ml·min^-1. The detector was set at 210 nm. Result： The retention time of mepivacaine and internal standard （ropivaeaine） was 7.4 min and 15.8min, respectively. The standard curve was linear over the concentration range of 20 to 4 000 ng·ml^-1. The lower limit of quantification was 20 ng·ml^-1. The method extraction recoveries were between 103.5% to 109. 2%. The intraand inter-day precisions were both less than 14.0%. Conclusion： This method is simple, sensitive, accurate and successfully applied in the pharmacokinetic study of mepivaeaine after epidural administration of 200 mg hydrochloride mepivacaine in a patient who needs surgical operation.