Mass Spectrometry Adduct Calculator

Blumer, Madison R.; Chang, Christine H.; Brayfindley, Evangelina RS; Nunez, Jamie; Colby, Sean M.; Renslow, Ryan S.; Metz, Thomas O.

doi:10.1021/acs.jcim.1c00579

DOE OSTI · 1837642

Mass Spectrometry Adduct Calculator

Blumer, Madison R.·Chang, Christine H.·Brayfindley, Evangelina RS·Nunez, Jamie·Colby, Sean M.·Renslow, Ryan S.·Metz, Thomas O.

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Abstract

We describe the Mass Spectrometry Adduct Calculator (MSAC), an automated Python tool to calculate the adduct ion masses of a parent molecule. Here, adduct refers to a version of a parent molecule [M] that is charged due to addition or loss of atoms and electrons resulting in a charged ion, e.g. [M+H] + . MSAC includes a database of 2,341 potential ions and their mass-to-charge ratios (m/z) as extracted from the NIST/EPA/NIH Mass Spectral Library (NIST17), the Global Natural Products Social Molecular Networking Public Spectral Libraries (GNPS), and MassBank of North America (MoNA). The calculator relies on user-selected subsets of the combined database to calculate expected m/z for adducts of molecules supplied as formulas This tool is intended to help researchers create identification libraries to collect evidence for the presence of molecules in mass spectrometry data. While the included adduct database focuses on adducts typically detected during liquid chromatography-mass spectrometry analyses, users may supply their own lists of adducts and charge states for calculating expected m/z. We also analyzed statistics on adducts from spectra contained in the three selected mass spectral libraries. MSAC is freely available at https://github.com/pnnl/MSAC.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY Adducts Biological databases Mass spectrometry Mathematical methods Molecules NIST 17

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Blumer, Madison R., Chang, Christine H., Brayfindley, Evangelina RS, Nunez, Jamie, Colby, Sean M., Renslow, Ryan S., Metz, Thomas O.. 2021-11-29. Mass Spectrometry Adduct Calculator. https://doi.org/10.1021/acs.jcim.1c00579

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