title: Liquid chromatography-electrospray ionisation mass spectrometry for the determination of nine selected benzodiazepines in human plasma and oral fluid.
abstract: A new simple and rapid liquid chromatographic-mass spectrometric technique was designed for the determination of nine benzodiazepines in plasma and oral fluid. Benzodiazepines were extracted from alkalinised spiked and clinical plasma and oral fluid samples using a single step, liquid-liquid extraction procedure with diethyl ether. The chromatographic separation was performed with a Xterra RP18, 5 microm (150 x 2.1 mm i.d.) reversed-phase column using deuterated analogues of the analytes as internal standard. The recovery ranged from 70.3 to 86.9% for plasma and 63.9 to 77.2% for oral fluid. The limits of detection ranged from 0.5 to 1 ng/ml in plasma and 0.1 to 0.2 ng/ml for oral fluid. The method was validated for all the compounds, including linearity and the main precision parameters. The procedure, showed to be sensitive and specific, was applied to real plasma and oral fluid samples. The method is especially useful to analyse saliva samples from drivers undergoing roadside drug controls.
authors.affiliation: Forensic Toxicology Service, Institute of Legal Medicine, University of Santiago de Compostela, C/San Francisco s/n, Santiago de Compostela, Spain.
authors.forename: O
authors.initials: O
authors.lastname: Quintela
authors.forename: A
authors.initials: A
authors.lastname: Cruz
authors.forename: A de
authors.initials: Ad
authors.lastname: Castro
authors.forename: M
authors.initials: M
authors.lastname: Concheiro
authors.forename: M
authors.initials: M
authors.lastname: López-Rivadulla
mesh_terms: D001569:Benzodiazepines / Q000097:blood / Q000493:pharmacokinetics*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D012015:Reference Standards; D015203:Reproducibility of Results; D012463:Saliva / Q000378:metabolism*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D001569:Benzodiazepines