... testing. In consumer healthcare, diabetics would be able to test theirglucose level, replacing painful and inconvenient finger-prick devices. For roadside screening of driv-ing impairment, a point-of-care ... source-drain bias voltage of 0.5 V. The current increased with the introduction of CO2gas. Thiswas due to the net positive charges increased on the gate area, thus inducing electrons in the 2DEGchannel. ... has been significant recent interest in the use of surface-functionalized thin film and nanowire wide bandgap semiconduc-tors, principally GaN, InN, ZnO and SiC, for sensing of gases, heavymetals,...