Identification of organic hydroperoxides and hydroperoxy acids in secondary organic aerosol formed during the ozonolysis of different monoterpenes and sesquiterpenes by on-line analysis using atmospheric pressure chemical ionization ion trap mass spectrometry.
On-line ion trap mass spectrometry (ITMS) enables the real-time characterization of reaction products of secondary organic aerosol (SOA). The analysis was conducted by directly introducing the aerosol particles into the ion source. Positive-ion chemical ionization at atmospheric pressure (APCI(+)) ITMS was used for the characterization of constituents of biogenic SOA produced in reaction-chamber experiments. APCI in the positive-ion mode usually enables the detection of [M+H](+) ions of the individual SOA components. In this paper the identification of organic peroxides from biogenic volatile organic compounds (VOCs) by on-line APCI-ITMS is presented. Organic peroxides containing a hydroperoxy group, generated by gas-phase ozonolysis of monoterpenes (alpha-pinene and beta-pinene) and sesquiterpenes (alpha-cedrene and alpha-copaene), could be detected via on-line APCI(+)-MS/MS experiments. A characteristic neutral loss of 34 Da (hydrogen peroxide, H(2)O(2)) in the on-line MS/MS spectra is a clear indication for the existence of an organic peroxide, containing a hydroperoxy functional group.
Institut für Anorganische Chemie und Analytische Chemie der Johannes Gutenberg-Universität Mainz, Duesbergweg 10-14, D-55099 Mainz, Germany.
Marc-Christopher
MC
Reinnig
Jörg
J
Warnke
Thorsten
T
Hoffmann
D000336:Aerosols / Q000737:chemistry; D000393:Air Pollutants / Q000737:chemistry*; D002264:Carboxylic Acids / Q000032:analysis*; D006861:Hydrogen Peroxide / Q000032:analysis*; D039821:Monoterpenes / Q000737:chemistry*; D009862:Online Systems; D010545:Peroxides / Q000032:analysis*; D011312:Pressure; D012717:Sesquiterpenes / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation / Q000379:methods*; D014835:Volatilization
D000336:Aerosols; D000393:Air Pollutants; D002264:Carboxylic Acids; D039821:Monoterpenes; D010545:Peroxides; D012717:Sesquiterpenes; D006861:Hydrogen Peroxide