title: Determination of LSD and N-demethyl-LSD in urine by liquid chromatography coupled to electrospray ionization mass spectrometry.
abstract: A sensitive and highly specific method for the determination of LSD and N-demethyl-LSD in urine, using combined liquid chromatography and mass spectrometry (LC-MS) with electrospray ionization, has been developed. Extrelut-3 extraction cartridges were used for a basic sample clean-up. Elution was obtained by toluene-diethyl ether (60:40, v/v). A Nucleosil C18 (150 X 1 mm I.D.) reversed-phase column was used for the chromatographic separation, together with a mixture of 2 mM ammonium formate buffer (pH 3) and acetonitrile (70:30, v/v) as mobile phase. Recoveries were 93 and 80%, detection limits 0.025 and 0.035 ng/ml for LSD and N-demethyl-LSD, respectively. Intra-assay precision, studied at four concentrations, was better than 9% at the ng/ml range and better than 14% at 0.10 ng/ml for both compounds. Limits of quantitation were 0.05 and 0.10 ng/ml for LSD and N-demethyl-LSD, respectively. Reproducibility was good and linearity excellent for LSD in the range from 0.05 to 20 ng/ml (r>0.9999, n=7).
authors.affiliation: Department of Pharmacology and Toxicology, University Hospital, Limoges, France.
authors.forename: H
authors.initials: H
authors.lastname: Hoja
authors.forename: P
authors.initials: P
authors.lastname: Marquet
authors.forename: B
authors.initials: B
authors.lastname: Verneuil
authors.forename: H
authors.initials: H
authors.lastname: Lotfi
authors.forename: J L
authors.initials: JL
authors.lastname: Dupuy
authors.forename: G
authors.initials: G
authors.lastname: Lachâtre
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D008238:Lysergic Acid Diethylamide / Q000031:analogs & derivatives* / Q000652:urine*; D013058:Mass Spectrometry / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: C058401:N-demethyllysergic acid diethylamide; D008238:Lysergic Acid Diethylamide