title: Determination of 21 drugs in oral fluid using fully automated supported liquid extraction and UHPLC-MS/MS.
abstract: Collection of oral fluid (OF) is easy and non-invasive compared to the collection of urine and blood, and interest in OF for drug screening and diagnostic purposes is increasing. A high-throughput ultra-high-performance liquid chromatography-tandem mass spectrometry method for determination of 21 drugs in OF using fully automated 96-well plate supported liquid extraction for sample preparation is presented. The method contains a selection of classic drugs of abuse, including amphetamines, cocaine, cannabis, opioids, and benzodiazepines. The method was fully validated for 200 μL OF/buffer mix using an Intercept OF sampling kit; validation included linearity, sensitivity, precision, accuracy, extraction recovery, matrix effects, stability, and carry-over. Inter-assay precision (RSD) and accuracy (relative error) were <15% and 13 to 5%, respectively, for all compounds at concentrations equal to or higher than the lower limit of quantification. Extraction recoveries were between 58 and 76% (RSD < 8%), except for tetrahydrocannabinol and three 7-amino benzodiazepine metabolites with recoveries between 23 and 33% (RSD between 51 and 52 % and 11 and 25%, respectively). Ion enhancement or ion suppression effects were observed for a few compounds; however, to a large degree they were compensated for by the internal standards used. Deuterium-labelled and13C-labelled internal standards were used for 8 and 11 of the compounds, respectively. In a comparison between Intercept and Quantisal OF kits, better recoveries and fewer matrix effects were observed for some compounds using Quantisal. The method is sensitive and robust for its purposes and has been used successfully since February 2015 for analysis of Intercept OF samples from 2600 cases in a 12-month period. Copyright © 2016 John Wiley & Sons, Ltd.
authors.affiliation: Norwegian Institute of Public Health, Drug Abuse Research, Lovisenberggata 6, Oslo, 0456, Norway.
authors.forename: Anja
authors.initials: A
authors.lastname: Valen
authors.affiliation: Norwegian Institute of Public Health, Drug Abuse Research, Lovisenberggata 6, Oslo, 0456, Norway.
authors.forename: Åse Marit
authors.initials: ÅM
authors.lastname: Leere Øiestad
authors.affiliation: Norwegian Institute of Public Health, Drug Abuse Research, Lovisenberggata 6, Oslo, 0456, Norway.
authors.forename: Dag Helge
authors.initials: DH
authors.lastname: Strand
authors.affiliation: Norwegian Institute of Public Health, Drug Abuse Research, Lovisenberggata 6, Oslo, 0456, Norway.
authors.forename: Ragnhild
authors.initials: R
authors.lastname: Skari
authors.affiliation: Norwegian Institute of Public Health, Drug Abuse Research, Lovisenberggata 6, Oslo, 0456, Norway.
authors.forename: Thomas
authors.initials: T
authors.lastname: Berg
mesh_terms: D000661:Amphetamine / Q000032:analysis; D000701:Analgesics, Opioid / Q000032:analysis; D001569:Benzodiazepines / Q000032:analysis; D002186:Cannabinoids / Q000032:analysis; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003042:Cocaine / Q000032:analysis; D006801:Humans; D013287:Illicit Drugs / Q000032:analysis*; D057230:Limit of Detection; D059625:Liquid-Liquid Extraction / Q000379:methods; D004364:Pharmaceutical Preparations / Q000032:analysis*; D015203:Reproducibility of Results; D012463:Saliva / Q000737:chemistry*; D015813:Substance Abuse Detection / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000701:Analgesics, Opioid; D002186:Cannabinoids; D013287:Illicit Drugs; D004364:Pharmaceutical Preparations; D001569:Benzodiazepines; D000661:Amphetamine; D003042:Cocaine
keywords: 13C-labelled internal standards; UHPLC-MS/MS; automated supported liquid extraction; drugs of abuse; oral fluid