title: Quantitation of lysergic acid diethylamide in urine using atmospheric pressure matrix-assisted laser desorption/ionization ion trap mass spectrometry.
abstract: A quantitative method was developed for analysis of lysergic acid diethylamide (LSD) in urine using atmospheric pressure matrix-assisted laser desorption/ionization ion trap mass spectrometry (AP MALDI-ITMS). Following solid-phase extraction of LSD from urine samples, extracts were analyzed by AP MALDI-ITMS. The identity of LSD was confirmed by fragmentation of the [M + H](+) ion using tandem mass spectrometry. The quantification of LSD was achieved using stable-isotope-labeled LSD (LSD-d(3)) as the internal standard. The [M + H](+) ion fragmented to produce a dominant fragment ion, which was used for a selected reaction monitoring (SRM) method for quantitative analysis of LSD. SRM was compared with selected ion monitoring and produced a wider linear range and lower limit of quantification. For SRM analysis of samples of LSD spiked in urine, the calibration curve was linear in the range of 1-100 ng/mL with a coefficient of determination, r(2), of 0.9917. This assay was used to determine LSD in urine samples and the AP MALDI-MS results were comparable to the HPLC/ ESI-MS results.
authors.affiliation: Institute for National Measurement Standards, National Research Council of Canada, Ottawa K1A 0R6, Canada.
authors.forename: Meng
authors.initials: M
authors.lastname: Cui
authors.forename: Margaret A
authors.initials: MA
authors.lastname: McCooeye
authors.forename: Catharine
authors.initials: C
authors.lastname: Fraser
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Mester
mesh_terms: D001274:Atmospheric Pressure; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D008238:Lysergic Acid Diethylamide / Q000652:urine*; D015394:Molecular Structure; D012680:Sensitivity and Specificity; D012996:Solutions / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D014867:Water / Q000737:chemistry
chemical_list: D012996:Solutions; D014867:Water; D008238:Lysergic Acid Diethylamide