During the last few years, interest in isotope ratio mass spectrometry (IRMS) has increased tremendously. IRMS is used for the determination of the origin/source of products and for adulteration detection. Application areas include natural product research, forensic and doping analysis (detection of endogenous versus exogenous origin of solutes).

Although IRMS is still often used for bulk analysis, the combination of IRMS with chromatographic separation is gaining a lot of attention, resulting in compound-specific isotope ratio determinations. Resolved solutes are directed towards a combustion oven for carbon or nitrogen isotope ratio determination or to a high temperature conversion oven for hydrogen or oxygen analysis.

GC-IRMS allows the analysis of more complex mixtures of solutes, but in order to successfully measure isotope ratios, isolation of target solutes is necessary. For this reason, the use of two-dimensional GC offers an important advantage compared to one-dimensional GC.

In this presentation, we will demonstrate a new configuration for GC-IRMS applying capillary flow technology and low thermal mass GC. As tobacco leaves and smoke are highly complex samples, these samples are very interesting for the evaluation of the two-dimensional GC-IRMS set-up. At first, the focus will be on the lipid fraction of these samples. Some data on isotope ratios obtained for tobacco leaves and their smoke analogues will be discussed.