Gas analysis in cell cultures and human breath

Research project P 14149 Gas Analysis in Cell Cultures and Human Breath Josef Rieder 06.03.2000 Breath analysis by measurement of volatile organic compounds (VOCs) can be used for diagnosis and therapy control of diseases. We use a very sensitive method to detect online these VOCs, namely Proton-Transfer-Reavtion Mass Spectrometry (PTR-MS), which has been developed at the Institute of Iron Physics (Innsbruck). To create standardized conditions for the investigation of metabolic processes, we shall apply an already developed standard protocoll for breath gas collection. Furthermore we shall use established cell cultures, e-g- HDMEC, HUVEC, HEPG2, to elucidate the physiological and pathophxsiological background of VOC origin and effects for the human organism. Cell-culture techniques are well defined and allow standardized measurements of emerging volatile products. During the last two years we conducted a number of provisional studies (exploiting the rare free capacity for PTR- MS measurements at the Institute of Ion Physics): * In screenings of patients with various malignomas (e.g. pancreatic carcinoma or bronchus carcinoma) we observed increased levels of volatile compounds with a mass of 107 daltons, but alsoincreased level of molecules with masses of 78, 106 and others. Mass 107 is the mass of o-toliudine, which is seen in PTR-MS protonated with a mass of 108 daltons. We demonstrated that this mass can be used as a highly significant marker (p<0.00000001) of different malignomas. * In a case report we could demonstrate that there is a linear correlation between the isoprene concentration in human breath and the cholesterol metabolism under lipid lowering therapy. The determination of ketones as well as isoprene in the breath offers a further tool for metabolic control in diabetes, because an increase in keton bodies indicates lipolysis and thus insulin deficiency or intensified fasting, and isoprene might be related to plasma lipid levels. * We showed that the highly sensitive PTR-MS method can detect minimal traces of anesthetic gases (isoflurane, sevoflurane). This allows to determine the occupational burden of anesthesists, nurses, surgeons and the exposure of patients undergoing general anesthesia using volatile anesthetics. Therefore we want to investigate whether PTR-MS is a useful, cheap and noninvasive method for screening, risk factor evaluation and therapy control in medicine.