Correlation between the synthetic origin of methamphetamine samples and their 15N and 13C stable isotope ratios

The active ingredient of ecstasy, N-methyl-3,4-methyldioxyphenylisopropylamine (MDMA) can be manufactured by a number of easy routes from simple precursors. We have synthesised 45 samples of MDMA following the five most common routes using N-precursors from 12 different origins and three different precursors for the aromatic moiety. The C-13 and N-15 contents of both the precursors and the MDMA samples derived therefrom were measured by isotope ratio mass spectrometry coupled to an elemental analyser (EA-IRMS). We show that within-pathway correlation between the N-15 content of the precursor and that of the derived MDMA can be strong but that no general pattern of correlation can be defined. Rather, it is evident that the delta N-15 values of MDMA are strongly influenced by a combination of the delta N-15 values of the source of nitrogen used, the route by which the MDMA is synthesised, and the experimental conditions employed. Multivariate analysis (PCA) based on the delta N-15 values of the synthetic MDMA and of the delta N-15 and delta C-13 values of the N-precursors leads to good discrimination between the majority of the reaction conditions tested. (c) 2007 Elsevier B.V. All rights reserved.