Post-source decay of alkylated and functionalized polycyclic aromatic compounds.

Fiche publication


Date publication

janvier 2007

Auteurs

Membres identifiés du Cancéropôle Est :
Dr VERNEX-LOSET Lionel


Tous les auteurs :
Frache G, Krier G, Vernex-Loset L, Muller JF, Manuelli P

Résumé

Post-source decay (PSD) is a valuable tool for providing structural information from large molecules by time-of-flight mass spectrometry (TOFMS). We used PSD to obtain this type of data from small molecules in the laser desorption/ionization (LDI) study of diesel engine exhaust particles. As the original nitrogen laser (lambda = 337 nm, E = 3.5 eV/photon) of our TOF mass spectrometer does not yield sufficient energy to ionize polycyclic aromatic hydrocarbons (PAHs), a second laser with a shorter wavelength has been coupled to the instrument. The fourth harmonic of a Nd:YAG laser (lambda = 266 nm, 4.6 eV/photon) has been chosen to achieve two-photon single-step desorption/ionization of PAHs. The PSD fragmentation of functionalized, alkylated and sulfur PAHs is discussed. Diesel engine exhaust particles are also studied as an example of a real complex sample. This technique is presented herein as a way to identify small molecules in environmental samples. Information provided by LDI-PSD-TOFMS can be a way to distinguish pollutants with very close molecular weights even if the resolving power of a TOF mass spectrometer is not sufficient.

Référence

Rapid Commun Mass Spectrom. 2007;21(16):2601-7.