Direct analysis of highly oxidised organic aerosol constituents by on-line ion trap mass spectrometry in the negative-ion mode.
On-line ion trap mass spectrometry (ITMS) enables the characterisation of constituents of biogenic secondary organic aerosols in complex organic reaction mixtures. This real-time analysis is achieved by directly introducing the airborne particles into the ion source of the mass spectrometer. Negative-ion chemical ionisation at atmospheric pressure (APCI(-)) was used as the ionisation method of choice. The aerosols were generated from the gas-phase ozonolysis of two C10H16-terpenes (alpha-pinene and limonene), and investigated by performing on-line APCI(-)-ITMS(n). Highly oxidised compounds were tentatively identified as important particle-phase products. Based on recent investigations of low-energy collision-induced dissociation pathways of a wide range of deprotonated multifunctional carboxylic acid species derived from monoterpene precursors (Warscheid B, Hoffmann T. Rapid Commun. Mass Spectrom. 2001; 15: 2259), the formation of structurally different C10H16O5 and C10H16O6 species, such as acidic esters from alpha-pinene and aldo-hydroxycarboxylic acids from limonene, is proposed.
Warscheid
Bettina
B
Institute of Spectrochemistry and Applied Spectroscopy (ISAS), P.O. Box 101352, 44013 Dortmund, Germany.
Hoffmann
Thorsten
T
D000336:Aerosols / Q000032:analysis*; D000081008:Bicyclic Monoterpenes; D053138:Cyclohexenes; D007477:Ions; D000077222:Limonene; D013058:Mass Spectrometry / Q000379:methods*; D039821:Monoterpenes; D009930:Organic Chemicals / Q000032:analysis*; D010084:Oxidation-Reduction; D010126:Ozone / Q000737:chemistry; D013729:Terpenes / Q000737:chemistry
D000336:Aerosols; D000081008:Bicyclic Monoterpenes; D053138:Cyclohexenes; D007477:Ions; D039821:Monoterpenes; D009930:Organic Chemicals; D013729:Terpenes; D010126:Ozone; D000077222:Limonene; C005451:alpha-pinene