Recent Accomplishments in Exhaled Breath Condensate Analysis - Molecular Aspects

Nowadays, the research of exhaled breath condensate (EBC) analysis is widely discussed in the scientific community. The growing interest in EBC analysis results is related to the ample advantages of non-invasive techniques in healthcare and related fields. In particular, EBC analysis can be used to diagnose respiratory diseases, monitor the disease's course during therapy, and monitor drug intake and metabolism. This review aims to systematize the accumulated knowledge on EBC collection, concentration, storage, and analysis methods and compare them with similar procedures for exhaled breath (EB). We proposed a generalized chemical classification of EBC compounds that are biomarkers for various diseases. The potential transformation of substances during EB condensation was considered, and EBC analysis methods were systematically categorized based on this classification. Methods for EBC analysis using chromatographic separation with mass spectrometric detection (hyphenated methods) were separately discussed as the most promising methods for future research applications.