"Skin gas" is unknowingly and constantly released and contains volatile organic compounds present in the blood, so it is useful as a sample for monitoring concentrations and components according to disease and metabolic conditions over time. It is believed that.However, there were many research issues such as the extremely low concentration and the need for measurements associated with different skin characteristics such as sweat gland density and number of epidermal layers depending on the body part.

　To solve these problems, the Group has developed the world's first gas imaging device (sniffing camera) that can observe the concentration distribution of blood volatile components released percutaneously in real time.We also developed a fitting device (two-dimensional true arc: Mako) that corrects the unevenness of the curved surface of the skin in order to realize accurate gas imaging even on the surface of the body with a complicated curved surface.

　As a demonstration experiment of this device, the concentration distribution of ethanol in the skin gas released from the subject after ingesting an alcoholic beverage and acetaldehyde, which is a metabolite, was imaged, and alcohol metabolism could be monitored non-invasively. It is said that it was.It was also found that, of the palms, fingers, backs, soles, and ears of the target parts, the region around the ears with less sweating and a thin epidermis was the most suitable part for measurement.

　The enzyme that reacts with alcohol and the biofluorescence method were used to detect ethanol and acetaldehyde, but it is also possible to image other gas species by changing the type of enzyme.For example, by visualizing acetone gas generated in diabetes and skin gas associated with skin cancer and breast cancer, it is expected to develop an early screening method for non-invasive diseases.

Paper information:[ACS Sensors] Transcutaneous blood VOC imaging system (skin-gas cam) with real-time bio-fluorometric device on rounded skin surface