Journal of Bioequivalence & Bioavailability

Abstract

Rapid and Sensitive Determination Of Montelukast in Human Plasma by High Performance Liquid Chromatographic Method Using Monolithic Column: Application to Pharmacokinetic Studies

Alireza Shafaati, Afshin Zarghi, Seyed Mohsen Foroutan, Arash Khoddam and Babak Madadian

A rapid, simple and sensitive high-performance liquid chromatography (HPLC) method, using a monolithic column and fluorescence detection, has been developed for quantification of montelukast in human plasma. Ethoxyquine, easily available as a pharmaceutical substance, was selected as internal satandard. The assay enables the measurement of montelukast for therapeutic drug monitoring with a minimum detectable limit of 5 ng/ ml−1. The method involves simple, one-step extraction procedure and analytical recovery was about 97%. The separation was carried out in reversed- phase conditions using a Chromolith RP® (RP-18e, 100 mm×4.6 mm) column at ambient temperature. The mobile phase was 56% acetonitrile and 50mM sodium dihydrogen phosphate, and distilled water to 100%, adjusted to pH 7.0 at a flow rate of 2 ml/min. The excitation wavelength was set at 350 nm, emission at 450 nm. The calibration curve was linear over the concentration range 20–800 ng/ml. The coefficients of variation for inter-day and intra-day assay were found to be less than 7%. The method was applied to the determination of montelukast in plasma from 12 subjects dosed with montelukast 10 mg tablets and pharmacokinetic parameters were determined.