Application of two‐step laser mass spectrometry to the chemical analysis of aerosol particle surfaces

Abstract

Two-step laser mass spectrometry (LZMS) was applied to study the chemical nature of adsorbates on aerosol particles which were collected from different sites, e.g. in the countryside, in an industrial zone, by a downtown road, and in a tunnel. The method combines infrared laser desorption from the particle surfaces followed by ultraviolet laser post-ionization of the desorbed neutral molecules. Because of the high sensitivity and optical selectivity of LZMS, virtually no sample preparation is needed, and mass spectra can be recorded in a very short time. Qualitative and quantitative comparisons of plycyclic aromatic hydrocarbons in different sampling areas were carried out. By scanning the ionization laser wavelength, two-dimensional UV/MS spectra can be generated for better identification of the adsorbed species.

Chemical characterization of particulate emissions from diesel engines: A review

“…NIST diesel PM (SRM 1650) was examined for PAHs by Hankin and John (1999), in this case using two UV lasers. Two lasers also make possible selective examination of internally mixed particles; thus, Zhan, Voumard, and Zenobi (2005) used one laser to desorb the adsorbed material on particles collected from rural, industrial, and roadway areas, and the second laser to ionize this material for mass spectral analysis.…”

Potential of laser mass spectrometry for the analysis of environmental dust particles—A review

“…Consequently, this configuration leads to an increase of the versatility of the experiments compared to LDI-MS. More specifically, the use of a tunable laser in the UV wavelength range demonstrated the ability of REMPI process to distinguish PAH isomers according to their gas phase spectroscopic properties. Thus, it was clearly demonstrated that a fine and specific control of the photoionization may be used to distinguish isomers [28,[115][116][117]. Desorption step also dependents on laser parameters.…”

“…First of all, as it was described in previous section, the yield of desorption/ionization or ablation/ionization process for organic and inorganic compound is highly dependent on the nature of the particulate matter: the so-called matrix effect. Chemical composition, particle morphology, optical properties and surface roughness affect the laser-particulate matter interaction and consequently, the yield of desorption or ablation [59,117,190].…”

“…L2MS was used to analyze aerosols collected from countryside, industrial zone and downtown road. For each of these particle types, a typical PAH pattern was obtained [117]. Tracers of diesel or gasoline vehicle exhaust aerosols have been clearly identified [121].…”

Évolution de la teneur en composés aromatiques des aérosols urbains au cours d'une journée. Étude par spectrométrie de masse à deux lasers

“…Des applications de la L2MS déjà décrites dans la littérature sont entre autres l'analyse de météorites [7,8], de sols [9], de polymères [10,11], de roches kérogènes [12], de marqueurs tumoraux [13], ou, justement, d'aérosols atmosphériques [14,15]. Des mesures quantitatives sont possibles sous certaines conditions [16,17].…”