Bad breath could generally mean someone ate a smelly lunch; however, it could also be a sign that the person is sick. Several scent compounds have been associated with illnesses such as lung cancer, diabetes, and Parkinson’s disease, causing researchers to design technology that measures these substances.
However, the challenge is developing instrumentation that can detect low, diagnostic levels of these disease biomarkers. Currently, researchers describe in ACS’ Analytical Chemistry a very sensitive “sniff-cam” that meets the requirement.
Before the dawn of modern technology, ancient medical practitioners used body and breath odor to diagnose illnesses. But healthy people also produce smelly volatile organic compounds (VOCs), and the levels of these substances can differ based on other factors, such as sex and body mass, so investigation can be complex.
Over the years, scientists have designed many different kinds of instruments to sense VOCs, such as ethanol (EtOH), a metabolite of the microbiome in humans that can offer an indication of glucose levels. But present-day systems to detect VOCs usually require large, costly equipment and trained specialists.
Previously, Kohji Mitsubayashi and colleagues designed a “bio-sniffer” that computed VOCs, such as acetone, a product of lipid metabolism. Lately, they demonstrated the first generation sniff-cam, which could visualize EtOH emissions from the skin of a person who had consumed alcohol. However, the team wanted to improve the device so it could sense diagnostic levels of biomarkers.
The scientists created a new version of the sniff-cam, which presently comprises a UV ring light, camera, and filters. An enzyme mesh, applied in the previous device, reacts EtOH with oxidized nicotinamide adenine dinucleotide (NAD), creating the fluorescent reduced form of NAD, which the camera records. A new imaging analysis technique enhanced the system’s sensitivity so that low amounts of EtOH could be measured.
The upgraded sniff-cam was then tested on a group of male subjects who had not taken any food or drink, and the device detected tiny levels of EtOH in their breath. These results indicate that the sniff-cam can envisage a wider range of VOC levels than earlier devices, and its versatility may help in the additional study of the association between scent and disease.