LC-MS法测定犬血浆中冬凌草甲素含量

LC-MS determination of oridonin in dog plasma

目的：建立犬血浆中冬凌草甲素浓度的LC-MS测定方法,为深入研究冬凌草甲素在犬体内的药代动力学特征提供有效、可靠的检测手段。方法：采用Shim-pack VP-ODS（150 mm×2.0 mm,5μm）色谱柱,以乙腈-水（50∶50）为流动相,HPLC/电喷雾离子源质谱检测（HPLC/ESI-MS）,乙酸乙酯作为萃取剂,检测犬血浆中冬凌草甲素的含量,并评价方法的稳定性和重现性。结果：本方法在0.0125-6.4μg.mL-1浓度范围内线性关系良好（R2=0.9994）,定量限为0.0125μg.mL-1,平均回收率为71.18%-76.99%,日内精密度为2.4%-5.0%,日间精密度为1.2%-6.3%。室温放置30 min,样品预处理后放置24 h、-24℃贮存14 d及反复冻融3次稳定性良好。其RSD均小于15%。结论：该分析方法可行性高,重现性好,可用于研究冬凌草甲素在犬体内药代动力学特征。

Objective：To establish an LC-MS method for quantitative determination of oridonin in dog plasma and provide a reliable method to evaluate the pharmacokinetics profile of oridonin in dogs.Methods：Shim-pack VP-ODS（150 mm×2.0 mm,5 μm） column,acetonitrile-water（50∶50）mobile phase system,HPLC/electrospray ionization mass spectrometric detection（HPLC/ESI-MS）,and acetic ether were developed to quantitatively determine oridonin in dog plasma.The stability and repeatability of the method were evaluated.Results：The assay was found to be linear for oridonin concentration in the range 0.0125 μg·mL-1 to 6.4 μg·mL^-1,with a lower limit of quantification of 0.0125 μg·mL-1.The extractive recovery was 71.18%-76.99%.The intra-day and inter-day precision of the method were 2.4%-5.0% and 1.2%-6.3% respectively.Stability studies indicated that oridonin in dog plasma was stable for 30 min at room temperature,24 h after sample pretreatment process,store at-24 ℃ for 14 days and was also stable over three freeze–thaw cycles.All of the relative standard deviation were less than 15% respectively.Conclusions：This method is highly feasible and reproducible.It may be a reliable technology to study pharmacokineties of oridonin in dogs.