Chinese Academy of Sciences: Online mass spectrometry detection progresses to improve organic identification

【Chinese instrument network instrument research and development】 Recently, Shen Chengyin, associate researcher of the spectrum and mass spectrometry research center of the Medical Physics and Technology Center of the Chinese Academy of Sciences' Hefei Institute of Material Science, has made progress in the research of organic matter on-line mass spectrometry technology, and the development of bipolar proton transfer reaction mass spectrometry ( DP-PTR-MS (new technology), through the positive and negative ions co-detection, can improve the identification of organic matter.

Bipolar proton transfer reaction mass spectrometry detection principle of organic matter

The study was published in the Journal of the American Society for Mass Spectrometry (DOI: 10.1007/s13361), entitled Detection of ketones by a novel technology: dipolar proton transfer reaction mass spectrometry (DP-PTR-MS). -017-1638-7).

For a long time, high-end on-line mass spectrometry technology, represented by Proton Transfer Reaction Mass Spectrometry (PTR-MS), has played an important role in the fields of environment, biology, medical and health, public safety, and the rapid quantification of trace volatile organic compounds (VOCs). Testing provides highly sensitive technical means. The working principle of PTR-MS is to convert VOC to [VOC+H]+ through the proton transfer reaction between the reactive ion H3O+ and the VOC of the analyte, so as to achieve VOC ionization and subsequent mass spectrometry detection. Due to the fact that the reactive ion H3O+ in the PTR-MS hardly reacts with inorganic substances, the proton extraction reaction mass spectrometry (PER-MS) technology was proposed in the earlier stage of the spectrum mass spectrometry laboratory, and the organic material was realized by preparing the negative reaction ion OH-. Simultaneous measurement with inorganics.

The bipolar proton transfer reaction mass spectrometry (DP-PTR-MS) technology developed by the researcher of the spectrum mass spectrometer has a switchable PTR-MS and a PER-MS operation mode. Enhanced organic identification capabilities. For example, when detecting ketone organic M, PTR-MS mode converts M to positive ion [M+H]+ (m/z ratio m+1), and PER-MS mode converts M to negative ion [MH]- (The charge-to-mass ratio is m-1.) Through the mutual demonstration of the unique change rule of the positive and negative ion charge-mass ratio in the two modes, the molecular weight of the ketone organic substance M to be measured can be accurately determined as m. The newly-developed DP-PTR-MS technology can not only detect organic/inorganic matter, but also improve the discriminating ability of organic matter.

This work has applied for invention patents and has been supported by the National Natural Science Foundation of China and the National Key R&D Program.

(Original Title: Latest Progress in Online Mass Spectrometry Detection Technology to Improve Organic Identification Ability)