Inter-laboratory comparison of elemental analysis and gas chromatography combustion isotope ratio mass spectrometry (GC-C-IRMS). Part I: δ13C measurements of selected compounds for the development of an isotopic Grob-test

✍ Scribed by F. Serra; A. Janeiro; G. Calderone; J. M. Moreno Rojas; C. Rhodes; L. A. Gonthier; F. Martin; M. Lees; A. Mosandl; S. Sewenig; U. Hener; B. Henriques; L. Ramalho; F. Reniero; A. J. Teixeira; C. Guillou

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 333 KB
• Volume: 42
• Category: Article
• ISSN: 1076-5174
• DOI: 10.1002/jms.1168

✦ Synopsis

Abstract

This study was directed towards investigating suitable compounds to be used as stable isotope reference materials for gas chromatography combustion isotope ratio mass spectrometry (GC‐C‐IRMS) calibration. Several compounds were selected from those used in the ‘Grob‐test’ mixture. Oxygen‐ and nitrogen‐containing substances were added to these compounds to allow the mixture to be used as a possible multi‐isotopic calibration tool for ^2^H/^1^H, ^13^C/^12^C, ^15^N/^14^N and ^18^O/^16^O ratio determinations. In this paper we present the results of δ^13^C measurements performed by the consortium of the five laboratories taking part in this inter‐calibration exercise. All the compounds were individually assessed for homogeneity, short‐term stability and long‐term stability by means of EA‐IRMS, as required by the bureau communitaire de reference (BCR) Guide for Production of Certified Reference Materials. The results were compared then with the GC‐C‐IRMS measurements using both polar and non‐polar columns, and the final mixture of selected compounds underwent a further certification exercise assessing limits of accuracy and reproducibility under specified GC‐C‐IRMS conditions. Copyright © 2007 John Wiley & Sons, Ltd.