A polydimethylsiloxane oral sampler was used to extract methanol, ethanol, ethylene glycol, 1,3-propandiol and γ-hydroxybutyric acid from samples of human saliva obtained using a passive drool approach. The extracted compounds were recovered by thermal desorption, isolated by gas chromatography and detected with differential mobility spectrometry, operating with a programmed dispersion field. Complex signal behaviours were also observed that were consistent with hitherto unobserved fragmentation behaviours in differential mobility spectrometry. These yielded high-mobility fragments obscured within the envelope of the water-based reactant ion peak. Further, compensation field maxima shifts were also observed which were attributable to transport gas modification phenomena. Nevertheless, the responses obtained indicated that in vivo saliva sampling with thermal desorption gas chromatography may be used to provide a semi-quantitative diagnostic screen over the toxicity threshold concentration ranges of 100 mg dm−3 to 3 g dm−3. A candidate method suitable for use in low resource settings for the non-invasive screening of patients intoxicated by alcohols and volatile sedatives has been demonstrated.

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Ion mobility spectrometry (IMS) provides quick and reliable responses when applied in the environmental field. However, when headspace (HS) is used as the sample introduction system, in some cases there may be a need to preconcentrate analyte if it is presented at low concentrations due to the low efficiency of HS. Herein, we discuss the parameters that affect the HS and the potential of combining solid phase extraction (SPE) and HS-IMS to improve the sensitivity of the method. The determination of phenol when it is presented in water or soil samples was selected as a case study and a limit of detection of 0.94 mg mL À1 and 0.14 mg mL À1 was obtained when direct analysis by HS-IMS was used. This methodology, which was developed based on SPE prior to HS-IMS analysis, was suitable for the detection of phenol at 0.05 mg mL À1 when 15 mL of water sample was passed through an HLB 60 mg SPE cartridge and eluted with 1 mL of dichloromethane. The HS-IMS analysis of the eluent in which phenol was present was carried out without any interference from the solvent.