A fingerprint of exhaled breath
04.04.2013 - Researchers from ETH Zurich have shown that the individual fingerprint of exhaled breath can be used for diagnostic purposes.
The team headed by Renato Zenobi reports in the journal PLoS that real-time analysis of the metabolic pattern found in exhaled breath can help to diagnose and monitor diseases. Using mass spectrometry (SESI-MS), the ETH researchers found that the chemical "fingerprint" of exhaled breath of 11 volunteers showed an individual core pattern and remained stable over time. According to the researchers, linking up that metabolic ID with genetic susceptibility to diseases can help diagnosing manifestation of diseases more individually. Shortly before, US researchers had published results of a MS-based study for diagnosis of heart failure.
"We did find some small variations during the day, but overall the individual pattern stays sufficiently constant to be useful for medical purposes," says Pablo Martinez-Lozano Sinues, senior scientist in Zenobi's research group. To carry out these measurements, Zenobi and his colleagues modified commercial mass spectrometers by adding a breath sampling inlet line that delivers exhaled breath from a mouth piece directly into the ion source of the instrument. Mass spectra showing peaks of roughly 100 compounds in breath can be easily and rapidly obtained.
The researchers are working to recognise characteristic patterns of lung diseases with the same technology. Although the potential usefulness of analysing breath for medical diagnosis has been known, it is rarely done in academic medicine. "This might be due to the fact that existing methods for breath analysis are either rather slow, or are limited to a small number of compounds that they can detect," says Sinues. Compared to analysis of blood or urine, a significant advantage of the ETH researchers’ approach is that the breath fingerprint is available within seconds. Another benefit is that exhaling into the ion source of a mass spectrometer is completely non-invasive. They researchers see huge potential to use the method as a tool for early detection of certain diseases in risk populations and in therapy monitoring.