Determination of febuxostat in human plasma using ultra‐performance liquid chromatography tandem mass spectrometry

A rapid and sensitive liquid chromatography‐tandem mass spectrometry method has been developed and validated for the determination of febuxostat in human plasma. The liquid‐liquid extraction technique was used for the extraction of febuxostat from human plasma using trandolapril as the internal standard (IS). Chromatography was performed on a ultra‐performance liquid chromatography (UPLC) BEH C18, 50 mm X 2.1 mm, 1.7 µm particle size column, with the mobile phase consisting of 0.1% formic acid and acetonitrile (in a 25:75 ratio), followed by detection using mass spectrometry. The method involves a simple reversed isocratic chromatography condition and mass spectrometry detection, which enables detection at sub‐microgram levels. The method was validated and the lower limit of quantification for febuxostat was found to be 0.075 µg/ml. The mean recovery for febuxostat ranged from 100.9 to 106.5%. This method increased the sensitivity and selectivity; resulting in high‐throughput analysis of febuxostat using commercially available IS for pharmacokinetic, bioavailability, and bioequivalence studies, with a chromatographic run time of 1.5 min only. Copyright © 2012 John Wiley & Sons, Ltd.