HPLC MS/MS method for quantification of meprobamate in human plasma: Application to 24/7 clinical toxicology

摘要

We described the development and full validation of rapid and accurate liquid chromatography method, coupled with tandem mass spectrometry detection, for quantification of meprobamate in human plasma with [~(13)C-~2H_3]-meprobamate as internal standard. Plasma pretreatment involved a one-step protein precipitation with acetonitrile. Separation was performed by reversed-phase chromatography on a Luna MercuryMS C18 (20mm×4mm×3μm) column using a gradient elution mode. The mobile phase was a mix of distilled water containing 0.1% formic acid and acetonitrile containing 0.1% formic acid. The selected reaction monitoring transitions, in electrospray positive ionization, used for quantification were 219.2→158.2 m/z and 223.1→161.1m/z for meprobamate and internal standard, respectively. Qualification transitions were 219.2→97.0 and 223.1→101.1 m/z for meprobamate and internal standard, respectively. The method was linear over the concentration range of 1-300mg/L. The intra- and inter-day precision values were below 6.4% and accuracy was within 95.3% and 103.6% for all QC levels (5, 75 and 200mg/L). The lower limit of quantification was 1mg/L. Total analysis time was reduced to 6min including sample preparation. The present method is successfully applied to 24/7 clinical toxicology and demonstrated its usefulness to detect meprobamate poisoning.