Biofluorometric gas sensors and imaging systems for human volatiles

Abstract

Biofluorometric gas sensors (bio-sniffers) for acetone and isopropanol were constructed by connecting a UV-LED and a photomultiplier tube to an optical-fiber with a flow-cell equipped S-ADH (secondary alcohol dehydrogenase) membrane. Gaseous acetone was measured by detecting the auto-fluorescence of NADH as a coenzyme of the S-ADH reaction. The breath acetone was analyzed by the bio-sniffer and thus, significantly higher diabetic acetone than that of healthy subjects was observed. Similarly, a volatile-imaging system (sniff-cam) for ethanol was also developed using an alcohol dehydrogenase mesh, a UV-LED array sheet and a CMOS-sensor, and successfully applied for imaging skin ethanol vapor after drinking. The sniff-cam allowed imaging of the ethanol distribution in the skin gas. The sniff-devices may be useful for non-invasive disease screening and assessment.