Real-Time High-Resolution Tandem Mass Spectrometry Identifies Furan Derivatives in Exhaled Breath

The identification of chemical compounds in exhaled human breath is promising in the search for new biomakers of diseases. However, the analytical techniques used nowadays are not capable of achieving a robust identification, especially in real-time analysis. In this work, we show that real-time high-resolution tandem mass spectrometry (HRMS/MS) is suitable for the identification of biomarkers in exhaled breath. Using this approach, we identified a number of furan derivatives, compounds found in the exhalome whose nature and origin are not yet clearly understood. It is also shown that the combination of HRMS/MS with UHPLC allowed not only the identification of the furan derivatives but also the proper separation of their isomeric forms.