title: Investigation of neuroleptics and other aromatic compounds by laser-based ion mobility mass spectrometry.
abstract: Laser-based ion mobility (IM) spectrometry was used for the detection of neuroleptics and PAH. A gas chromatograph was connected to the IM spectrometer in order to investigate compounds with low vapour pressure. The substances were ionized by resonant two-photon ionization at the wavelengths λ = 213 and 266 nm and pulse energies between 50 and 300 μJ. Ion mobilities, linear ranges, limits of detection and response factors are reported. Limits of detection for the substances are in the range of 1-50 fmol. Additionally, the mechanism of laser ionization at atmospheric pressure was investigated. First, the primary product ions were determined by a laser-based time-of-flight mass spectrometer with effusive sample introduction. Then, a combination of a laser-based IM spectrometer and an ion trap mass spectrometer was developed and characterized to elucidate secondary ion-molecule reactions that can occur at atmospheric pressure. Some substances, namely naphthalene, anthracene, promazine and thioridazine, could be detected as primary ions (radical cations), while other substances, in particular acridine, phenothiazine and chlorprothixene, are detected as secondary ions (protonated molecules). The results are interpreted on the basis of quantum chemical calculations, and an ionization mechanism is proposed.
authors: Physical Chemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany.
authors: C
authors: C
authors: Brendler
authors: D
authors: D
authors: Riebe
authors: T
authors: T
authors: Ritschel
authors: T
authors: T
authors: Beitz
authors: H-G
authors: HG
authors: Löhmannsröben
mesh_terms: D014150:Antipsychotic Agents / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006841:Hydrocarbons, Aromatic / Q000032:analysis*; D007834:Lasers; D057230:Limit of Detection; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
chemical_list: D014150:Antipsychotic Agents; D006841:Hydrocarbons, Aromatic