Breathomics: May it Become an Affordable, New Tool for Early Diagnosis and Screening of Lung Cancer?

Patients were asked to orally exhale 1-2 L breath into a 5 L Tedlar bag via a one-way mouthpiece and Nafion filter for moisture removal, as shown in Figure 1B. The process usually takes about a few minutes. The breath analysis took place either in-situ immediately after the breath sample collection or within 24 h of breath collection. The Tedlar bags were stored under ambient condition until analyzed. During the breath analysis, the Tedlar bag was connected to the sampling port of the portable GC (Figure 1C). Approximately 350 mL of breath was pulled from the Tedlar bag into the GC for analysis. The GC operation was controlled using LabView via a laptop. The total assay time was 30 min, including 5 min of breath sampling time from the Tedlar bag at a flow rate of 70 mL/min (see the blue path in Figure 1A), 5 min of desorption/transfer time, 10 min of chromatographic separation time (see the orange path in Figure 1A), and 10 min of GC system cleaning time.