title: Two-dimensional ultra-thin-layer chromatography and atmospheric pressure matrix-assisted laser desorption/ionization mass spectrometry in bioanalysis.
abstract: The feasibility of ultra-thin-layer chromatography (UTLC) and atmospheric pressure matrix-assisted laser desorption/ionization mass spectrometry (AP-MALDI-MS) for bioanalysis was studied with benzodiazepines as model substances in human urine. Two-dimensional (2D) UTLC was shown to be an efficient technique for the separation of benzodiazepines. Separations occurred in 4-12 min, and the separated compounds were identified by AP-MALDI-MS. The limits of detection with AP-MALDI-MS and AP-MALDI-MS/MS were in the picomole range and thus low enough for bioanalysis. The applicability of the 2D UTLC-AP-MALDI-MS was demonstrated in detection of metabolites with an authentic biological urine sample.
authors.affiliation: Faculty of Pharmacy, Division of Pharmaceutical Chemistry, and Drug Discovery and Development Technology Center, University of Helsinki, Helsinki, Finland.
authors.forename: Piia K
authors.initials: PK
authors.lastname: Salo
authors.forename: Suvi
authors.initials: S
authors.lastname: Vilmunen
authors.forename: Hannele
authors.initials: H
authors.lastname: Salomies
authors.forename: Raimo A
authors.initials: RA
authors.lastname: Ketola
authors.forename: Risto
authors.initials: R
authors.lastname: Kostiainen
mesh_terms: D001274:Atmospheric Pressure; D001569:Benzodiazepines / Q000302:isolation & purification / Q000652:urine*; D002855:Chromatography, Thin Layer / Q000379:methods*; D006801:Humans; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
chemical_list: D001569:Benzodiazepines