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A reliable method for measuring (15)N/(14)N and (2)H/(1)H ratios of nicotine in cigarette tobacco has been developed. It involves a simple procedure for extracting nicotine from tobacco using methanol. The extract is directly analyzed on a gas chromatography isotope ratio mass spectrometer (GC-IRMS). The method is reproducible with 4% RSD for delta(2)H and delta(15)N. Brand name cigarettes manufactured in Canada (N = 47) and in China (N = 23) have been analyzed. The results show that nicotine from Canadian cigarettes has a higher (2)H/(1)H ratio and a lower (15)N/(14)N ratio than the Chinese cigarettes. The delta(2)H values for Canadian cigarettes range from -232.7 per thousand to -203.4 per thousand with an average of -222.1 per thousand; the delta(2)H values for Chinese cigarettes range from -262.6 per thousand to -219.9 per thousand with an average of -243.8 per thousand. The delta(15)N values for Canadian cigarettes range from -7.7 per thousand to -6.3 per thousand with an average of -7.1 per thousand; the delta(15)N values for Chinese cigarettes range from -7.6 per thousand to -5.7 per thousand with an average of -6.3 per thousand. The combined measurements of (2)H/(1)H and (15)N/(14)N have been shown to be useful in identifying counterfeits of Canadian cigarettes analyzed in this study.

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Ion mobility spectroscopy (IMS)-based trace-compound detectors (TCDs) are powerful and widely implemented tools for the detection of illicit substances. They combine high sensitivity, reproducibility, rapid analysis time, and resistance to dirt with an acceptable false alarm rate. The analytical specificity of TCD-IMS instruments for a given analyte depends strongly on a detailed knowledge of the ion chemistry involved, as well as the ability to translate this knowledge into field-robust analytical methods. In this work, we introduce an enhanced hybrid TCD-IMS/mass spectrometer (TCD-IMS/MS) that combines the strengths of ion-mobility-based target compound detection with unambiguous identification by tandem MS. Building on earlier efforts along these lines (Kozole et al., Anal. Chem. 2011, 83, 8596-8603), the current instrument is capable of positive and negative-mode analyses with tightly controlled gating between the IMS and MS modules and direct measurement of ion mobility profiles. We demonstrate the unique capabilities of this instrument using four samples of opium seized by the Canada Border Services Agency (CBSA), consisting of a mixture of opioid alkaloids and other naturally occurring compounds typically found in these samples. Although many analytical methods have been developed for analyzing naturally occurring opiates, this is the first detailed ion mobility study on seized opium samples. This work demonstrates all available analytical modes for the new IMS-MS system including "single-gate", "dual-gate", MS/MS, and precursor ion scan methods. Using a combination of these modes, we unambiguously identify all signals in the IMS spectra, including previously uncharacterized minor peaks arising from compounds that are common in raw opium.

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