Determination of N-nitrosodimethylamine in artificial gastric juice by gaschromatography-mass spectrometry and by gas chromatography-thermal energy analysis

The thermal energy analyser (TEA) is considered to be the gold standard for the determination of nitrosamines. However, since many laboratories cannot justify the use of such a very specific detection system, alternative dete ction methods are useful. While standard gas chromatography (GC) detectors lack the selectivity of the TEA detector, mass spectrometry (MS) seems to b e the method of choice to combine GC separation with mass selective detecti on. Moreover, the detection limits of the GC-MS assay in general use are ab out 4 times lower than those of the GC-TEA assay. A comparison of GC-MS and GC-TEA data on N-nitrosodimethylamine determinations showed a strong corre lation between the two assays (R-2 = 0.86), demonstrating the exchangeabili ty of these methods. (C) 2001 Lippincott Williams & Wilkins.