Reliable and Precise Determination of Montelukast in Human Plasma by UPLC-MS/MS

Abstract

A reliable, selective and precise ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/ MS) method is developed for the determination of montelukast in human plasma. The analyte and montelukast-d6 as an internal standard were extracted from plasma (100 µL) by liquid-liquid extraction. Chromatographic analysis was carried out on UPLC BEH C18 (50 mm × 2.1 mm, 1.7 µm) column under isocratic conditions using acetonitrile-3.0 mM ammonium formate, pH 4.0 adjusted with 0.1 % formic acid (90:10, v/v) as the mobile phase. For MS/MS quantitation in the positive ESI mode, the pre- cursor → product ion (m/z 586.1 → 422.1) transition was monitored for montelukast. The assay was linear in the concentration range of 0.05 - 200 ng/mL, while the chromatographic run time for the analysis was 1.2 min. The extraction recovery was within 95-98 % across four quality control samples. The precision (% coefficient of variation) and accuracy of the method ranged from 1.01 to 6.56 % and 97.2 to103.7 % respectively. Additionally, the method was validated for matrix effect, stability in plasma and whole blood and ruggedness. The method was efficiently used for a bioequivalence study of montelukast in 30 healthy subjects and the assay reproducibility was demonstrated by reanalysis of 131 incurred samples.