Influence of condensing equipment and temperature on exhaled breath condensate pH, total protein and leukotriene concentrations

Summary Background Exhaled breath condensate analysis is an attractive but still not fully standardised method for investigating airway pathology. Adherence of biomarkers to various condensing surfaces and changes in condensing temperature has been considered to be responsible for the variability of the results. Our aims were to compare the efficacy of different types of condensers and to test the influence of condensing temperature on condensate composition. Methods Breath condensates from 12 healthy persons were collected in two settings: (1) by using three condensers of different type (EcoScreen, R-Tube, Anacon) and (2) by using R-Tube condenser either cooled to −20 or −70 °C. Condensate pH at standardised CO2 level was determined; protein content was measured by the Bradford method and leukotrienes by EIA. Results Breath condensates collected using EcoScreen were more alkaline (6.45±0.20 vs. 6.19±0.23, p