Sorbent-coated metal discs: A hybrid active/passive exhaled breath sampling alternative for early lung cancer screening

In this new breath sampling method, a metal disc with carbopack X sorbent was exposed to prolonged exhalation. Sampled volatile organic compounds (VOCs) were transferred to a solid phase micro-extraction (SPME) fiber for gas chromatography-mass spectrometry (GC-MS) analysis. The performance of these discs was compared to breath biomarker extraction by SPME from Tedlar® bags. Ten commonly reported breath biomarkers were selected as targets (acetone, isoprene, toluene, hexanal, benzaldehyde, decane, octanal, nonanal, dodecane and decanal). The new method proved significantly better at extracting the latter eight of the ten target compounds. The two methods were also evaluated by exposing the sorbent disc and an SPME fiber to a mixture of seven VOCs. The sorbent discs extracted the standard compounds more efficiently, yielding 2-9 times larger GC-MS signals for the four last-eluting compounds than direct SPME. In conclusion, the new sorbent disc method can, with minimal effort from patients, extract VOCs from breath more efficiently than the current state-of-the-art.