title: Comprehensive two-dimensional gas chromatography, a valuable technique for screening and semiquantitation of different chemical compounds in ultrafine 30 nm and 50 nm aerosol particles.
abstract: Comprehensive two dimensional gas chromatography-time-of-flight mass spectrometry (GC×GC-TOF-MS) was used for screening and semiquantitation of semivolatile organic compounds in aerosol particles. As the volatility was a prerequisite parameter for the analysis, some compounds were transformed via derivatization such as silylation into more volatile ones. The identification of the analytes was made by comparing the GC retention indices and the TOF mass spectra with the NIST and the Golm metabolome database reference libraries. The data treatment was simplified by exploiting an additional classification of the identified compounds, namely the main functional group or specific element present in the molecule leading to different groups of compounds. This methodology was applied to identify compounds in 30 ± 4 nm, 50 ± 5 nm and total suspended particles (TSP) collected during spring and autumn of 2009 and summer of 2010 at the Station for Measuring Forest Ecosystem Atmosphere Relations (SMEAR II) at Hyytiälä (Finland). The number of identified compounds was higher than 400, which were the most relevant compounds present in the samples, in terms of concentrations. The analysis of aerosol particles of different sizes, collected simultaneously, revealed that the number of compounds increased with the particle size whereas the normalized response factor decreased in most of the cases, aldehydes being an exception. This decrease could be associated with the formation or aggregation of new compounds onto the particles when they grow in the atmosphere.
authors.affiliation: Laboratory of Analytical Chemistry, Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 University of Helsinki, Finland.
authors.forename: José
authors.initials: J
authors.lastname: Ruiz-Jiménez
authors.forename: Jevgeni
authors.initials: J
authors.lastname: Parshintsev
authors.forename: Totti
authors.initials: T
authors.lastname: Laitinen
authors.forename: Kari
authors.initials: K
authors.lastname: Hartonen
authors.forename: Marja-Liisa
authors.initials: ML
authors.lastname: Riekkola
authors.forename: Tuukka
authors.initials: T
authors.lastname: Petäjä
authors.forename: Markku
authors.initials: M
authors.lastname: Kulmala
mesh_terms: D000336:Aerosols / Q000737:chemistry*; D000393:Air Pollutants / Q000032:analysis*; D004784:Environmental Monitoring / Q000295:instrumentation / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry / Q000295:instrumentation / Q000379:methods*; D010316:Particle Size; D052638:Particulate Matter / Q000737:chemistry*; D055549:Volatile Organic Compounds / Q000032:analysis*
chemical_list: D000336:Aerosols; D000393:Air Pollutants; D052638:Particulate Matter; D055549:Volatile Organic Compounds