DH2.1 - Isoprene Selective Gas Sensing by Adsorption Filter
- 17th International Meeting on Chemical Sensors - IMCS 2018
2018-07-15 - 2018-07-19
- Sensors for Diagnostics and Health Care 2
- J. van den Broek, A. Güntner, S. Pratsinis - Particle Technology Laboratory, ETH Zurich, Zurich (Switzerland)
- 145 - 146
Isoprene is a promising breath marker for the non-invasive monitoring of high blood cholesterol. However, portable gas sensors (e.g. metal-oxide based), do not offer the required selectivity to detect isoprene levels in complex human breath. Here, we present a new filter concept enabling fast and highly selective detection of isoprene at the ppb level and high humidity. The filter is a packed bed of activated alumina powder placed upstream of a non-specific Pt-doped SnO2 sensor. Hydrophilic breath compounds (e.g. acetone, ammonia, ethanol, methanol) are adsorbed and retained on the adsorbent during detection of hydrophobic isoprene, which is not affected by the filter. This way, isoprene is measured within seconds in simulated breath with unprecedented selectivity >100 to the tested analytes. Full regeneration of the filter within 10 min by purging with air enables continuous application, promising for portable breath isoprene analyzers.