1 research outputs found
Fluorometric Sniff-Cam (Gas-Imaging System) Utilizing Alcohol Dehydrogenase for Imaging Concentration Distribution of Acetaldehyde in Breath and Transdermal Vapor after Drinking
Understanding concentration distributions,
release sites, and release
dynamics of volatile organic compounds (VOCs) from the human is expected
to lead to methods for noninvasive disease screening and assessment
of metabolisms. In this study, we developed a visualization system
(sniff-cam) that enabled one to identify a spatiotemporal change of
gaseous acetaldehyde (AcH) in real-time. AcH sniff-cam was composed
of a camera, a UV-LED array sheet, and an alcohol dehydrogenase (ADH)-immobilized
mesh. A reverse reaction of ADH was employed for detection of gaseous
AcH where a relationship between fluorescence intensity from nicotinamide
adenine dinucleotide and the concentration of AcH was inversely proportional;
thus, the concentration distribution of AcH was measured by detecting
the fluorescence decrease. Moreover, the image differentiation method
that calculated a fluorescence change rate was employed to visualize
a real-time change in the concentration distribution of AcH. The dynamic
range of the sniff-cam was 0.1–10 ppm which encompassed breath
AcH concentrations after drinking. Finally, the sniff-cam achieved
the visualization of the concentration distribution of AcH in breath
and skin gas. A clear difference of breath AcH concentration was observed
between aldehyde dehydrogenase type 2 active and inactive subjects,
which was attributed to metabolic capacities of AcH. AcH in skin gas
showed a similar time course of AcH concentration to the breath and
a variety of release concentration distribution. Using different NADH-dependent
dehydrogenases in the sniff-cam could lead to a versatile method for
noninvasive disease screening by acquiring spatiotemporal information
on various VOCs in breath or skin gas