Citation

Iitani K, Sato T, Naisierding M, Hayakawa Y, Toma K, Arakawa T, Mitsubayashi K. Anal. Chem. 2018; 90(4): 2678-2685.

Copyright

(Copyright © 2018, American Chemical Society)

DOI

10.1021/acs.analchem.7b04474

PMID

29359564

Abstract

Understanding concentration distributions, release sites and release dynamics of 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 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 inverse proportion; thus, the concentration distribution of AcH was measured by detecting the fluorescence decrease. Moreover, image differentiation method that calculated a fluorescence change rate was employed to visualize a real-time change in the concentration distribution of AcH. A dynamic range of the sniff-cam was 0.1-10 ppm that encompassed breath AcH concentrations after drinking. Finally, the sniff-cam achieved to visualize 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 of various VOCs in breath or skin gas.

Language: en