• human breath
• diagnosis
• analysis

Over the last few years, breath analysis for monitoring metabolic disorders caused by specific diseases has become more and more attractive due to its non-invasiveness. Several approaches have been proposed for sample collection, treatment, and analysis, mainly devoted to the qualitative evaluation of various chemical compounds.
This experimental thesis has been devoted to the development of optimized analytical procedures for the quantitative determination of several chemical compounds in human breath samples. The sampling system has been optimized by comparing some of the materials that the bags are made of: Nalophan was selected both for its low cost and a very low sample contamination. The optimized analytical procedure includes analyte pre-concentration in adsorption tubes: TenaxGR and sodium sulphate were the most suitable stationary phase and the most effective water adsorbent, respectively. The adsorption tubes were connected on-line with a GC-MS system for the determination of the compounds of interest.
Finally, the optimized analytical procedure was applied to the analysis of breath samples gathered from patients with two types of disease, namely diabetes and hepatic cirrhosis. The preliminary results were very promising, and would seem to indicate that this monitoring technique could be used in clinical applications.