Dr. Renato Zenobi, ETH-Zurich
Seminar title “Exhalomics - on-line medical diagnosis via mass spectrometric analysis of exhaled breath”
Host: Dr. Schultz
On-line breath analysis is a powerful approach to obtain insight into the metabolism of a person in real time. With ambient ionization methods, this can be achieved rapidly and completely non-invasively, opening up interesting possibilities to diagnose diseases via exhaled breath, to discern diurnal changes in the metabolism, and to monitor drug use (or drug abuse) by analyzing the chemical composition of exhaled breath.
The technical background of the methodology, secondary electrospray ionization - high resolution mass spectrometry (SESI-HRMS), will first be explained, including the analytical performance (mass resolution, upper mass limit, detection limit, softness of ionization, etc.) and the coverage of biomarkers (polarity, volatility, molecular weight, etc.) that can be detected. SESI-HRMS affords sub-ppt limits of detection, and analysis of compounds with molecular weights up to 1000 Da, and thus excellent coverage of the breath metabolome and deep insight into the metabolic state of a person. High mass resolution and tandem mass spectrometry also allows detailed characterization of compounds that can be used as biomarkers, often aided by chromatography, of exhaled breath condensate and comparison against commercially available or synthetic reference compounds.
Several applications for medical diagnosis will then be presented. These include the detection of novel biomarkers for respiratory diseases such as obstructive sleep apnea (OSA), chronic obstructive pulmonary disease (COPD), cystic fibrosis, and asthma. Monitoring of metabolic changes during sleep, of drug compliance and of pharmacokinetics, and of covid-19 infections via real-time SESI-HRMS will also be discussed.