This study aimed to develop a highly selective, sensitive and fast liquid chromatography tandem mass spectrometric (LC–MS/MS) method for the determination of obacunone in rat plasma. Sample preparation was accomplished by a simple solid‐phase extraction procedure. Chromatographic separation was carried out on an ACQUITY BEH C₁₈ column using acetonitrile/methanol (1:1, v/v) and 0.1% formic acid in water as mobile phase at a flow rate of 0.4 mL/min. Quantification was performed with multiple reactions monitoring in positive ion mode with the precursor‐to‐product ion transitions at m/z 455.2 > 161.1 for obacunone and m/z 515.2 > 161.1 for nomilin (internal standard). The assay was demonstrated to be linear over the concentration range of 0.1–1,000 ng/mL with correlation coefficient >0.999 (r > 0.999). The intra‐ and inter‐day accuracy ranged from −8.33 to 10.40%, while the precision was <10.41%. The mean extraction recovery was >75.32%, and the assay was free of matrix effect. The validated LC–MS/MS method was successfully applied to the pharmacokinetic study of obacunone in rats after oral and intravenous administrations. The oral bioavailability of obacunone was 13.59%.

中文翻译：

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固相萃取-液相色谱串联质谱法选择性，可靠地测定大鼠血浆中的奥巴香酮：在药代动力学研究中的应用

这项研究的目的是开发一种高选择性，灵敏，快速的液相色谱串联质谱法（LC-MS / MS），用于测定大鼠血浆中的奥贝康酮。样品制备是通过简单的固相萃取程序完成的。色谱分离是在ACQUITY BEH C ₁₈色谱柱上进行的，使用乙腈/甲醇（1：1，v / v）和0.1％的甲酸水溶液作为流动相，流速为0.4 mL / min。通过正离子模式下的多个反应监测进行定量，奥巴酮和m / z的前体离子到产物离子的跃迁为m / z 455.2> 161.1Nomilin（内部标准）为515.2> 161.1。实验证明，在0.1–1,000 ng / mL的浓度范围内，该测定是线性的，相关系数> 0.999（r  > 0.999）。日内和日间准确度在−8.33到10.40％之间，而准确度在<10.41％之间。平均提取回收率> 75.32％，测定无基质效应。经验证的LC-MS / MS方法已成功地应用于大鼠口服和静脉内给药的ac豆酮的药代动力学研究。奥巴酮的口服生物利用度为13.59％。