Protomer Formation Can Aid the Structural Identification of Caffeine Metabolites
| العنوان: | Protomer Formation Can Aid the Structural Identification of Caffeine Metabolites |
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| المؤلفون: | Sepman, Helen, Tshepelevitsh, Sofja, Hupatz, Henrik, Kruve, Anneli |
| المصدر: | Analytical Chemistry. 94(30):10601-10609 |
| الوصف: | The structural annotation of isomeric metabolites remains a key challenge in untargeted electrospray ionization/high-resolution mass spectrometry (ESI/HRMS) metabolomic analysis. Many metabolites are polyfunctional compounds that may form protomers in electrospray ionization sources and therefore yield multiple peaks in ion mobility spectra. Protomer formation is strongly structure-specific. Here, we explore the possibility of using protomer formation for structural elucidation in metabolomics on the example of caffeine, its eight metabolites, and structurally related compounds. It is observed that two-thirds of the studied compounds formed high- and low-mobility species in high-resolution ion mobility. Structures in which proton hopping was hindered by a methyl group at the purine ring nitrogen (position 3) yielded structure-indicative fragments with collision-induced dissociation (CID) for high- and low-mobility ions. For compounds where such a methyl group was not present, a gas-phase equilibrium could be observed for tautomeric species with two-dimensional ion mobility. We show that the protomer formation and the gas-phase properties of the protomers can be related to the structure of caffeine metabolites and facilitate the identification of the structural isomers. |
| وصف الملف: | |
| URL الوصول: | https://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-209464 https://doi.org/10.1021/acs.analchem.2c00257 |
| قاعدة البيانات: | SwePub |
Find this issue from the American Chemical Society | تدمد: | 00032700 15206882 |
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| DOI: | 10.1021/acs.analchem.2c00257 |