HPLC测定犬血浆中甲基斑蝥胺及其药代动力学研究

Determination of plasma concentration of N-methylcantharidimide by HPLC and its pharmacokinetics after intravenous administration in dogs

目的:建立犬血浆中甲基斑蝥胺的HPLC测定法,测定犬静脉注射甲基斑蝥胺后的血药浓度,并对其药代动力学进行评价。方法:血浆样品加入适量甲醇提取进行HPLC分析,流动相乙腈-水(35∶65),流速0.7mL·min-1,检测波长212nm。犬静脉注射10,15,20mg·kg-1的3个剂量甲基斑蝥胺后,测定血浆中不同时间点甲基斑蝥胺的浓度,并计算主要药动学参数。结果:血浆中甲基斑蝥胺在0.01～10.0mg·L-1线性关系良好,血浆中甲基斑蝥胺的最低检测限为0.01mg·L-1,平均回收率92.3%,日内和日间差异RSD均小于10%,峰面积与血药浓度呈良好的线性关系(r=0.9963)。犬分别静脉注射3个剂量甲基斑蝥胺后,各剂量组相对应的t1/2α分别为1.8,2.1,1.7min,t1/2β分别为144,139,146min。结论:本实验方法简便、可靠,可用于甲基斑蝥胺血药浓度分析及其药代动力学研究,测定结果可为该药的临床用药提供依据。

Objectives：To establish a HPLC method for determination of N-methylcantharidimide in dogs′ plasma and to study the pharmacokinetics of N-methylcantharidimide in dogs′. Method： The plasma samples were extracted by methanol. The acetonitrile and the purified water composed mobile phase. The flow rate was 0.7 mL·min-1, ultraviolet detection wavelength was at 212 nm. Result： The calibration curve was linear over the range from 0.01-10.0 mg·L-1 with a correlation coefficiency of 0.996 3. The lower limit of quantitation was 0.01 mg·L-1.the mean recovery was 92.3%. the relative standard deviation（RSD）of intra-day and inter-day were all less than 10%. After intravenous administration of N-methylcantharidimide with 3 dosages of 10, 15, 20 mg·kg-1 to dogs, the corresponding distribution half-livers（t1/2α） were 1.8,2.1,1.7 min, and the elimination half-lives （t1/2β） were 144,139,146 min, respectively. Conclusion：This method is convenient, accurate and reliable. It can be used for determination of N-methylcantharidimide in dogs′ plasma and pharmacokinetic studies.