Simultaneous quantification of alprazolam, 4- and α-hydroxyalprazolam in plasma samples using liquid chromatography mass spectrometry

A sensitive and specific method was developed for quantification of alprazolam and its two metabolites 4-hydroxyalprazolam and α-hydroxyalprazolam in plasma. The work up procedure was solid phase extraction. Liquid chromatography–mass spectrometry (LC–MS) was used for separation, detection and quantification of the analytes. The limit of quantitation (LOQ) was 0.05 ng/mL for alprazolam and the two metabolites. The extraction recovery was more than 82% for alprazolam and its metabolites. The within- and between-assay coefficients of variation were in the range of 1.9–17.9%. The method was used for determination of the pharmacokinetics parameters of alprazolam and its two metabolites in healthy Caucasian subjects who ingested 1 mg of alprazolam.