Determination of biomarker IL-6 in exhaled breath condensate using exhaled breath condensate collector

Background and Objective: The collection of exhaled breath condensate (EBC) is a noninvasive, safe and simple technique to obtain direct samples from lung and use for estimation of the effects of air pollution on human subjects. EBC contains several compounds including simple ions, hydrogen peroxide, proteins, cytokines, deoxyribonucleic acid (DNA), creatine, Electrolytes, trace elements and toxic metals that are diluted by water vapor. The objective of this study was to determine biomarker IL-6 in exhaled breath condensate using an exhaled breath condensate collector. Materials and Methods: The collector was designed and built and was used for collection and condensation of exhaled breath. EBC was taken from 36 young participants. Each person was asked to breathe for 10-15 min and the condensate was kept in a vial. The samples of exhaled breath were cooled down to -20 °C using the collector. The exhaled breath was converted to the solid/liquid mixture and then, the biomarker IL-6 was measured with ELISA (Enzyme -linked immunosorbent assay) method using HS600B R&D Kit. Results: The mean concentration of IL-6 was 1.08 pg/mL in collected samples. The standard deviation of IL-6 concentration was 0.47. Moreover, the average volume of collected EBC was 2.3 mL, ranged between 0.3 and 3.5 mL. Conclusion: The results of this study showed that the volume of the exhaled breath condensate was comparable with similar commercial devices. The average concentration of interlukin-6 was similar to the concentrations reported by other studies. Based on the findings, this equipment can be used by researchers as a suitable device for measurement of IL-6 in exhaled breath condensate