Development and validation of a liquid chromatographic/electrospray ionization mass spectrometric method for the quantitation of prazepam and its main metabolites in human plasma

✍ Scribed by Paraskevi Valavani; Julia Atta-Politou; Irene Panderi

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 191 KB
• Volume: 40
• Category: Article
• ISSN: 1076-5174
• DOI: 10.1002/jms.824

✦ Synopsis

Abstract

A method was developed and fully validated for the quantitation of prazepam and its major metabolites, oxazepam and nordiazepam, in human plasma. Sample pretreatment was achieved by solid‐phase extraction using Oasis HLB cartridges. The extracts were analysed by high‐performance liquid chromatography (HPLC) coupled with single‐quadrupole mass spectrometry (MS) with an electrospray ionization interface. The MS system was operated in the selected ion monitoring mode. HPLC was performed isocratically on a reversed‐phase XTerra MS C~18~ analytical column (150 × 3.0 mm i.d., particle size 5 µm). Diazepam was used as the internal standard for quantitation. The assay was linear over a concentration range of 5.0–1000 ng ml^−1^ for all compounds analyzed. The limit of quantitation was 5 ng ml^−1^ for all compounds. Quality control samples (5, 10, 300 and 1000 ng ml^−1^) in five replicates from three different runs of analysis demonstrated an intra‐assay precision (CV) of ≤9.1%, an inter‐assay precision of ≤6.0% and an overall accuracy (relative error) of <4.6%. The method can be used to quantify prazepam and its metabolites in human plasma covering a variety of pharmacokinetic or bioequivalence studies. Copyright © 2005 John Wiley & Sons, Ltd.