Performance Evaluation of EA-IRMS Methods for the Determination of the D/H Ratio in Tetramethylurea and Other Compounds - Results of a Laboratory Inter-Comparison

Tetramethylurea (TMU) with a certified D/H ratio is the internal standard for SNIF NMR(r) analysis of wine ethanol for detection of possible adulterations (Commission Regulation 2676/90). A new batch of a TMU certified reference material (CRM) is currently prepared. Whereas SNIF NMR was employed up to now, 2H EA IRMS was envisaged as the method of choice for value assignment of the new CRM, as more precise (better repeatable) data might be obtained, resulting in lower uncertainty of the certified value. In order to evaluate the accuracy, intra- and inter-laboratory reproducibility of 2H EA IRMS methods, a laboratory inter-comparison was carried out by analysing TMU, other organic compounds as well as some waters. The results revealed that experienced laboratories are capable of generating robust and well comparable data, which highlights the emerging potential of IRMS in food authenticity testing. However, a systematic bias between IRMS and SNIF NMR reference data was observed for TMU; this lack of data consistency rules out the 2H IRMS technique for the characterisation measurements of the new TMU CRM.

BREAS Olivier;  THOMAS Freddy;  ZELENY Reinhard;  CALDERONE Giovanni;  JAMIN Eric;  GUILLOU Claude; 

2007-08-02

JOHN WILEY & SONS LTD

JRC37039

https://publications.jrc.ec.europa.eu/repository/handle/JRC37039,   

10.1002/rcm.2988,