title: Online volatile organic compound measurements using a newly developed proton-transfer ion-trap mass spectrometry instrument during New England Air Quality Study--Intercontinental Transport and Chemical Transformation 2004: performance, intercomparison, and compound identification.
abstract: We have used a newly developed proton-transfer ion-trap mass spectrometry (PIT-MS) instrument for online trace gas analysis of volatile organic compounds (VOCs) during the 2004 New England Air Quality Study-Intercontinental Transport and Chemical Transformation study. The PIT-MS instrument uses proton-transfer reactions with H3O+ ions to ionize VOCs, similarto a PTR-MS (proton-transfer reaction mass spectrometry) instrument but uses an ion trap mass spectrometer to analyze the product ions. The advantages of an ion trap are the improved identification of VOCs and a near 100% duty cycle. During the experiment, the PIT-MS instrument had a detection limit between 0.05 and 0.3 pbbv (S/N = 3 (signal-to-noise ratio)) for 2-min integration time for most tested VOCs. PIT-MS was used for ambient air measurements onboard a research ship and agreed well with a gas chromatography mass spectrometer). The comparison included oxygenated VOCs, aromatic compounds, and others such as isoprene, monoterpenes, acetonitrile, and dimethyl sulfide. Automated collision-induced dissociation measurements were used to determine the contributions of acetone and propanal to the measured signal at 59 amu; both species are detected at this mass and are thus indistinguishable in conventional PTR-MS.
authors.affiliation: National Oceanic and Atmospheric Administration, Aeronomy Laboratory, 325 Broadway, Boulder, Colorado 80305, USA. Carsten.Warneke@noaa.gov
authors.forename: Carsten
authors.initials: C
authors.lastname: Warneke
authors.forename: Shuji
authors.initials: S
authors.lastname: Kato
authors.forename: Joost A
authors.initials: JA
authors.lastname: De Gouw
authors.forename: Paul D
authors.initials: PD
authors.lastname: Goldan
authors.forename: William C
authors.initials: WC
authors.lastname: Kuster
authors.forename: Min
authors.initials: M
authors.lastname: Shao
authors.forename: Edward R
authors.initials: ER
authors.lastname: Lovejoy
authors.forename: Ray
authors.initials: R
authors.lastname: Fall
authors.forename: Fred C
authors.initials: FC
authors.lastname: Fehsenfeld
mesh_terms: D000392:Air Movements; D000393:Air Pollutants / Q000032:analysis*; D001331:Automation; D004784:Environmental Monitoring / Q000379:methods*; D020407:Internet; D013058:Mass Spectrometry / Q000379:methods*; D009511:New England; D009930:Organic Chemicals / Q000032:analysis; D014835:Volatilization
chemical_list: D000393:Air Pollutants; D009930:Organic Chemicals