Comparison of carbon isotope ratio measurement of the vanillin methoxy group by gc-irms and 13c-qnmr

• Verfasst von: Greule, Markus [VerfasserIn]
• Verfasst von: Le, Phuong Mai [VerfasserIn]
• Verfasst von: Meija, Juris [VerfasserIn]
• Verfasst von: Mester, Zoltán [VerfasserIn]
• Verfasst von: Keppler, Frank [VerfasserIn]
• Titel: Comparison of carbon isotope ratio measurement of the vanillin methoxy group by gc-irms and 13c-qnmr
• Verf.angabe: Markus Greule, Phuong Mai Le, Juris Meija, Zoltán Mester, and Frank Keppler
• Jahr: 2024
• Umfang: 6 S.
• Illustrationen: Illustrationen, Diagramme
• Fussnoten: Im Titel ist 13 hochgestellt ; Published online 28 November 2023, published in issue 3 January 2024 ; Gesehen am 14.03.2024
• Titel Quelle: Enthalten in: American Society for Mass SpectrometryJournal of the American Society for Mass Spectrometry
• Ort Quelle: Washington, DC : ACS Publications, 1990
• Jahr Quelle: 2024
• Band/Heft Quelle: 35(2024), 3, Seite 100-105
• ISSN Quelle: 1879-1123
• DOI: doi:10.1021/jasms.3c00327
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1883470242

Abstract

Site-specific carbon isotope ratio measurements by quantitative 13C NMR (13C-qNMR), Orbitrap-MS, and GC-IRMS offer a new dimension to conventional bulk carbon isotope ratio measurements used in food provenance, forensics, and a number of other applications. While the site-specific measurements of carbon isotope ratios in vanillin by 13C-qNMR or Orbitrap-MS are powerful new tools in food analysis, there are a limited number of studies regarding the validity of these measurement results. Here we present carbon site-specific measurements of vanillin by GC-IRMS and 13C-qNMR for methoxy carbon. Carbon isotope delta (δ13C) values obtained by these different measurement approaches demonstrate remarkable agreement; in five vanillin samples whose bulk δ13C values ranged from −31‰ to −26‰, their δ13C values of the methoxy carbon ranged from −62.4‰ to −30.6‰, yet the difference between the results of the two analytical approaches was within ±0.6‰. While the GC-IRMS approach afforded up to 9-fold lower uncertainties and required 100-fold less sample compared to the 13C-qNMR, the 13C-qNMR is able to assign δ13C values to all carbon atoms in the molecule, not just the cleavable methoxy group.