E-Nose Sensing of Low-ppb Formaldehyde in Gas Mixtures at High Relative Humidity for Breath Screening of Lung Cancer?

• DOI: 10.1021/acssensors.6b00008
• Publication Date: 2016-03-01T10:33:03Z
• Authors: Andreas T. Güntner; Vitaly Koren; Kiran Chikkadi; Marco Righettoni; Sotiris E. Pratsinis
• Keywords: Electronic Nose; Breath gas analysis

Formaldehyde (FA) is a potential breath marker for lung cancer and tracer indoor air quality monitoring. Its typical concentrations are below 100 ppb posing sensitivity selectivity challenge to current portable sensor systems. Here, we present highly sensitive, selective, compact electronic nose (E-nose) real-time quantification of FA at realistic conditions. This E-nose consists four nanostructured porous Pt-, Si-, Pd-, Ti-doped SnO2 sensing films directly deposited onto silicon wafer-based microsubstrates by flame spray pyrolysis (FSP). The constituent sensors offer stable responses (24 h tested) detection down 3 (signal-to-noise ratio > 25) breath-realistic 90% relative humidity. Each dopant induces different analyte enabling selective in two-, three- four-analyte mixtures multivariate linear regression. In simulated (FA with higher acetone, NH3, ethanol concentrations), detected an average error ≤ 9 using the overcoming issues single sensors. device could facilitate easy screening patients monitoring concentrations.