Methane chemical ionization of pesticides by ion-trap technology: Spectral characteristics and data precision

Abstract. An airborne chemical ionization ion trap mass spectrometer instrument (CI-ITMS) has been developed for tropospheric and stratospheric fast in-situ measurements of PAN (peroxyacetyl nitrate) and PPN (peroxypropionyl nitrate). The first scientific deployment of the FASTPEX instrument (FASTPEX = Fast Measurement of Peroxyacyl nitrates) took place in the Arctic during 18 missions aboard the DLR research aircraft Falcon, within the framework of the POLARCAT-GRACE campaign in the summer of 2008. The FASTPEX instrument is described and characteristic properties of the employed ion trap mass spectrometer are discussed. Atmospheric data obtained at altitudes of up to ~12 km are presented, from the boundary layer to the lowermost stratosphere. Data were sampled with a time resolution of 2 s and a 2σ detection limit of 25 pmol mol−1. An isotopically labelled standard was used for a permanent online calibration. For this reason the accuracy of the PAN measurements is better than ±10% for mixing ratios greater than 200 pmol mol−1. PAN mixing ratios in the summer Arctic troposphere were in the order of a few hundred pmol mol−1 and generally correlated well with CO. In the Arctic boundary layer and lowermost stratosphere smaller PAN mixing ratios were observed due to a combination of missing local sources of PAN precursor gases and efficient removal processes (thermolysis/photolysis). PPN, the second most abundant PAN homologue, was measured simultanously. Observed PPN/PAN ratios range between ~0.03 and 0.3.

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Nitric Oxide Chemical Ionization Ion Trap Mass Spectrometry for the Determination of Automotive Exhaust Constituents

Analytical Chemistry ◽

10.1021/ac970841x ◽

1997 ◽

Vol 69 (24) ◽

pp. 5121-5129 ◽

Cited By ~ 8

Author(s):

Mark A. Dearth ◽

Keiji G. Asano ◽

Kevin J. Hart ◽

Michelle V. Buchanan ◽

Douglas E. Goeringer ◽

...

Keyword(s):

Nitric Oxide ◽

Mass Spectrometry ◽

Chemical Ionization ◽

Ion Trap ◽

Ion Trap Mass Spectrometry ◽

Automotive Exhaust

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Determination of Carbadox-Related Residues in Swine Liver by Gas Chromatography/Mass Spectrometry with Ion Trap Detection

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/74.4.611 ◽

1991 ◽

Vol 74 (4) ◽

pp. 611-618 ◽

Cited By ~ 6

Author(s):

Martin J Lynch ◽

Franklyn R Mosher ◽

Richard P Schneider ◽

Hassan G Fouda ◽

James E Risk

Keyword(s):

Chemical Ionization ◽

Ion Trap ◽

Internal Standard ◽

Gas Chromatography Mass Spectrometry ◽

Isotope Dilution Analysis ◽

Gas Chromatograph ◽

Porcine Liver ◽

Methyl Ester Derivative ◽

Swine Liver

Abstract The Ion trap detector (ITD), in combination with a capillary gas chromatograph and under chemical ionization conditions, offers sufficient sensitivity to determine carbadoxrelated residues as the methyl ester derivative of quinoxaline- 2-carboxylic acid at 3 μg/kg or higher in porcine liver. A tetradeuterated internal standard of QME effectively compensates for losses incurred during sample preparation. The method produced mean levels of 3.3 (±0.5), 5.5 (±0.8), and 10.1 (±0.9) μg/kg for liver fortified at 3, 5, and 10 μg/kg. When applied to analysis of samples containing incurred residues of 14C-carbadox at the low μg/kg level, results were comparable to those obtained by reverse isotope dilution analysis.

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