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Updated: Feb 3, 2026

Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
Electron Attachment Reaction Ionization of Gas-Phase Methylglyoxal
Xue-Wei Lu1,2,3, Yi Ren1,2,3, Qing-Yu Liu1,3
1State Key Laboratory for Structural Chemistry of Unstable and Stable Species , Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190 , P. R. China.
Abstract:
Methylglyoxal (MGLY) plays a significant role in atmospheric chemistry by serving as a key contributor to the formation of active free radicals, ozone, and secondary organic aerosol. Detection of MGLY by traditional chemical ionization such as proton-transfer reaction has several shortcomings such as parent molecule fragmentation. In this study, an electron attachment reaction (EAR) ionization method has been developed for the effective detection of MGLY. Almost no fragmentation was observed during the EAR. The generation of MGLY- anion in the EAR was further confirmed by cryogenic photoelectron imaging spectroscopy. The concentration of MGLY can be calibrated by using dibromomethane (CH2Br2) as reference gas. The detection sensitivity of MGLY was estimated to be (100 ± 2) mV/ppbv (parts per billion by volume). The O2, H2O, CO2, and trace gases in ambient air have no obvious effects on the detection of MGLY- anion by the EAR ionization method.
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