title: Applications of Hadamard transform-gas chromatography/mass spectrometry to online detection of exhaled breath after drinking or smoking.
abstract: A Hadamard transform-gas chromatography/mass spectrometry (HT-GC/MS) technique was employed for the online detection of ethanol or toluene in exhaled breath after drinking or smoking, respectively. Exhaled breath samples, collected from volunteers, were directly injected into the GC inlet by a Hadamard-injector without any pretreatment. In the case of breath from a drinker, using a conventional single injection, a small ion peak (corresponding to approximately 0.1 ng of ethanol), the intensity of which was approximately equal to or less than the limit of detection. When the HT technique was applied, the signal-to-noise (S/N) ratio was dramatically improved. Furthermore, in the case of breath from a smoker, using conventional injection, a weak ion peak (corresponding to approximately 0.7 pg of toluene) was marginally detected. However, the HT technique led to an improvement in the S/N ratio, with the peak corresponding to the limit of detection. In both cases, the HT technique permitted specific components in exhaled breath to be determined, without the need for any extraction procedures.
authors.affiliation: Department of Chemistry, National Taiwan Normal University, 88 Sec. 4, Tingchow Road, Taipei, Taiwan.
authors.forename: Yuan-Kai
authors.initials: YK
authors.lastname: Cheng
authors.forename: Cheng-Huang
authors.initials: CH
authors.lastname: Lin
authors.forename: Takashi
authors.initials: T
authors.lastname: Kaneta
authors.forename: Totaro
authors.initials: T
authors.lastname: Imasaka
mesh_terms: D000428:Alcohol Drinking / Q000378:metabolism*; D001944:Breath Tests / Q000379:methods*; D004867:Equipment Design; D000431:Ethanol / Q000032:analysis; D005583:Fourier Analysis; D008401:Gas Chromatography-Mass Spectrometry / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D012680:Sensitivity and Specificity; D012907:Smoking / Q000378:metabolism*; D014050:Toluene / Q000032:analysis
chemical_list: D014050:Toluene; D000431:Ethanol