METHOD DEVELOPMENT AND VALIDATION FOR THE ESTIMATION OF AMPRENAVIR IN HUMAN PLASMA BY LIQUID CHROMATOGRAPHY–ELECTROSPRAY IONIZATION–TANDEM MASS SPECTROMETRY

Objective: The main aim of the present study was to develop a sensitive liquid chromatography–electrospray ionization–tandem mass spectrometric technique for the quantitation of amprenavir in human plasma. Methods: Chromatographic separation was achieved on a reversed-phase Symmetry C18 (50 mm×4.6 mm, 3.5 μm) column with isocratic elution by acetonitrile and 0.1% v/v formic acid in the ratio of 90:10 v/v as mobile phase. Chromatographic peaks were resolved with 0.7 ml/min flow rate. Drug was extracted with ethyl acetate solvent by liquid–liquid extraction method. Monitoring of transition of m/z 506.2 and 71.0 for amprenavir and 628 and 421 for methyl-indinavir was made on multiple reaction monitoring. Results: Calibration curve of amprenavir was linear over 1–600 ng/ml concentration range with regression coefficient (r2) value of >0.99. The % relative standard deviation values were <8.5% for interday and intraday precision and accuracy. The method has excellent recovery, and the percentage recovery values of lower quality control (QC), median QC, and higher QC samples were 101.86%, 102.8%, and 99.28%, respectively. Conclusion: The drug was stable for more time at variable stability conditions, and method was successfully applicable to regular analysis of amprenavir in biological matrices