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Solid-phase microextraction (SPME) is a popular sampling technique in which chemical compounds are collected with a sorbent-coated fiber and then desorbed into an analytical instrument such as a liquid or gas chromatograph. Typically, this technique is used to sample the headspace above a solid or liquid sample (headspace SPME), or to directly sample a liquid (immersion SPME). However, this work demonstrates an alternative approach where the sample is totally vaporized (total vaporization SPME or TV-SPME) so that analytes partition directly between the vapor phase and the SPME fiber. The implementation of this technique is demonstrated with polydimethylsiloxane-divinylbenzene (PDMS-DVB) and polyacrylate (PA) coated SPME fibers for the collection of nicotine and its metabolite cotinine in chloroform extracts. The most important method parameters were optimized using a central composite design, and this resulted in an optimal extraction temperature (96 °C), extraction time (60 min), and sample volume (120 μL). In this application, large sample volumes up to 210 μL were analyzed using a volatile solvent such as chloroform at elevated temperatures. The sensitivity of TV-SPME is nearly twice that of liquid injection for cotinine and nearly 6 times higher for nicotine. In addition, increased sampling selectivity of TV-SPME permits detection of both nicotine and cotinine in hair as biomarkers of tobacco use where in the past the detection of cotinine has not been achieved by conventional SPME.

In 2009, the R. J. Reynolds Tobacco Co. released a line of dissolvable tobacco products that are marketed as an alternative to smoking in places where smoking is prohibited. These products are currently available in Indianapolis, IN, Columbus, OH, and Portland, OR. This paper describes the chemical characterization of four such products by gas chromatography-mass spectrometry (GC-MS). The dissolvable tobacco products were extracted and prepared by ultrasonic extraction using acetone, trimethylsilyl derivatization, and headspace solid phase microextraction (SPME). The following compounds were identified in the dissolvables using either ultrasonic extractions or trimethylsilyl derivatization: nicotine, ethyl citrate, palmitic acid, stearic acid, sorbitol, glycerol, and xylitol. The following compounds were identified in the dissolvables using headspace SPME: nicotine, ethyl citrate, cinnamaldehyde, coumarin, vanillin, and carvone. With the exception of nicotine, the compounds identified thus far in the dissolvables are either flavoring compounds or binders. The concentration of free nicotine in the dissolvables was determined from the Henderson-Hasselbalch equation and by measuring the pH and nicotine concentration by GC-MS. The results presented here are the first to reveal the complexity of dissolvable tobacco products and may be used to assess potential oral health effects.

Objectives: This pilot study investigated the accuracy of onsite immunoassay urinalysis of illicit drug use in 42 outpatients with co-occurring substance use disorders and serious mental illness., Methods: Up to 40 urine samples were submitted by each participant as part of a larger study investigating the efficacy of contingency management in persons with co-occurring disorders. Each sample was analyzed for the presence of amphetamine, methamphetamine, cocaine, marijuana, and opiates or their metabolites using onsite qualitative immunoassays. One onsite urinalysis was randomly selected from each participant for confirmatory gas chromatography-mass spectrometry (GC-MS) analyses., Results: Agreement between immunoassay and GC-MS was calculated. Agreement was high, with 98% agreement for amphetamine, methamphetamine, opiate, and marijuana. Agreement for cocaine was 93%., Conclusions: Results of this pilot study support the use of onsite immunoassay screening cups as an assessment and outcome measure in adults with serious mental illness., Scientific Significance: Data suggest that onsite urinalysis screenings may be a helpful assessment tool for measuring clinical and research outcomes., (Copyright © Informa Healthcare USA, Inc.)