Vaka Venkata Rami Reddy, Inamadugu Jaswanth Kumar, Pilli Nageswara Rao, Ramesh Mullangi, Katreddi Hussain Reddy
Bioanalytical Department, Apotex Research Pvt. Ltd, Bangalore, India; Department of Chemistry, Sri Krishna Devaraya University, Anantapur, 515055, India.
Biomed Chromatogr. 2013 Nov;27(11):1406-12. doi: 10.1002/bmc.2936. Epub 2013 Jun 4.
An improved, simple and highly sensitive LC-MS/MS method has been developed and validated for quantification of febuxostat with 100 μL human plasma using febuxostat-d7 as an internal standard (IS) according to regulatory guidelines. The analyte and IS were extracted from human plasma via liquid-liquid extraction using diethyl ether. The chromatographic separation was achieved on a Zorbax C18 column using a mixture of acetonitrile and 5 mm ammonium formate (60:40, v/v) as the mobile phase at a flow rate of 0.5 mL/min. The total run time was 5.0 min and the elution of febuxostat and IS occurred at 1.0 and 1.5 min, respectively. A linear response function was established for the range of concentrations 1-6000 ng/mL (r > 0.99). The precursor to product ion transitions monitored for febuxostat and IS were m/z 317.1 → 261.1 and 324.2 → 262.1, respectively. The intra- and inter-day precisions (%RSD) were within 1.29-9.19 and 2.85-7.69%, respectively. The proposed method was successfully applied to pharmacokinetic studies in humans.
根据监管指南，已开发并验证了一种改进的、简单且高灵敏度的液相色谱-串联质谱（LC-MS/MS）方法，用于以非布司他-d7作为内标（IS），对100 μL人血浆中的非布司他进行定量分析。通过使用乙醚进行液-液萃取，从人血浆中提取分析物和内标。在Zorbax C18柱上进行色谱分离，以乙腈和5 mM甲酸铵（60:40，v/v）的混合物作为流动相，流速为0.5 mL/min。总运行时间为5.0分钟，非布司他和内标的洗脱时间分别为1.0分钟和1.5分钟。建立了浓度范围为1-6000 ng/mL的线性响应函数（r > 0.99）。非布司他和内标监测的前体离子到产物离子的转变分别为m/z 317.1 → 261.1和324.2 → 262.1。日内和日间精密度（%RSD）分别在1.29-9.19%和2.85-7.69%范围内。所提出的方法已成功应用于人体药代动力学研究。
