Department of Analytical Chemistry, Palacký University, 17. listopadu 12, CZ-771 46 Olomouc, Czech Republic.
J Chromatogr A. 2011 Nov 4;1218(44):7996-8001. doi: 10.1016/j.chroma.2011.09.001. Epub 2011 Sep 8.
A simple, fast and sensitive HPLC method with electrochemical detection employing boron-doped diamond electrode (BDD) for the determination of sildenafil (Viagra™), vardenafil (Levitra™) and their main metabolites, N-desmethyl sildenafil and N-desethyl vardenafil in human plasma is presented. The assay involved drug extraction by tert-butyl methyl ether and isocratic reversed-phase liquid chromatography with amperometric detection. Complete separation of all analytes was achieved within 12 min. The mobile phase consisted of 20mM sodium dihydrogen phosphate with 40 mM sodium perchlorate/acetonitrile (70:30, v/v), pH 3.5. The electrode working potential was +1520 mV (vs. Pd/H(2)). Calibration curves were linear over the concentration range of 10-400 ng mL(-1). Phloretin was used as an internal standard. The limits of detection (LOD) and quantification (LOQ) for the studied analytes were within the range of 2-4 ng mL(-1) and 7.0-13.4 ng mL(-1), respectively. The developed method was applied to human plasma samples spiked with analytes at therapeutic concentrations. The study confirms the method's suitability for both pharmacokinetic studies and therapeutic monitoring.
本文介绍了一种简单、快速、灵敏的 HPLC 方法，采用电化学检测，使用掺硼金刚石电极（BDD），可同时测定人血浆中的西地那非（伟哥）、伐地那非（艾力达）及其主要代谢物 N-去甲基西地那非和 N-去乙基伐地那非。该方法采用叔丁基甲醚提取药物，等度反相液相色谱-安培检测。所有分析物在 12 分钟内完全分离。流动相由 20mM 磷酸二氢钠和 40mM 高氯酸钠/乙腈（70:30，v/v）组成，pH 值为 3.5。工作电极电位为+1520 mV（相对于 Pd/H2）。校准曲线在 10-400ng mL-1 浓度范围内呈线性。根皮苷被用作内标。研究分析物的检测限（LOD）和定量限（LOQ）分别在 2-4ng mL-1 和 7.0-13.4ng mL-1 范围内。所建立的方法适用于在治疗浓度下添加分析物的人血浆样品。该研究证实了该方法适用于药代动力学研究和治疗监测。
