空Topic:Wearable Biosensors and Volatile Biomarker Imaging System: Toward Real-Time, Non-Invasive Monitoring of Human Health

Takahiro Arakawa

Tokyo University of Technology

Abstract：The measurement of biophysical quantities of the human body has garnered significant attention in the medical and healthcare fields. Wearable sensors have emerged as promising tools for monitoring relevant parameters in healthcare, sports, and medical applications. Leveraging biophysical information with these systems is expected to enable proactive health management, thereby improving public health and reducing medical expenditure. This paper discusses two types of wearable biosensors: tear and saliva glucose biosensors. Our group has developed soft contact lens biosensors for tear chemicals and oral cavity biosensors, such as mouthguard biosensors for salivary analysis. Challenges related to integrating biosensors into monitoring biological information and daily medicine are also addressed. Moreover, recent advancements in analytical devices have facilitated the measurement of minute amounts of odorous materials and volatile chemical compounds. Human breath and skin volatiles, including gases from halitosis and body odor, contain compounds indicative of metabolic processes and specific ailments. Measurement of these volatile biological compounds holds promise for simplifying metabolic capacity evaluation, medical diagnostics, and disease screening. We have developed a novel two-dimensional fluorometric imaging system for detecting ethanol vapor released from human breath and palm skin. This imaging system measures ethanol vapor concentrations by analyzing the fluorescence intensity of nicotinamide adenine dinucleotide (NADH) through an enzymatic reaction induced by alcohol dehydrogenase. The NADH fluorometric imaging system enables real-time, two-dimensional imaging of ethanol vapor distribution at ppb concentration levels. We applied this imaging system to measure breath ethanol vapor and skin ethanol vapor from a human palm, demonstrating rapid and accurate responses with visible measurements. This technology holds promise for real-time analysis of metabolism function in the near future.

Biography：Dr. Takahiro Arakawa is currently a Professor at the Department of Electric and Electronic Engineering, Tokyo University of Technology, since 2025. He had served as an Associate Professor at the same department since 2021. He received his BS and MS degrees from Waseda University in 2002 and 2004, respectively. He completed the Ph.D. program in Nanoscience and Nanoengineering and received his Ph.D. degree for research on “Microfluidic system for single cell analysis” from Waseda University in 2007. In 2008, he joined the Laboratory of Bioanalytical Chemistry at the University of Tokyo as a Postdoctoral Research Fellow of the Japan Society for the Promotion of Science (JSPS, PD). Since 2009, he served as an Assistant Professor at Tokyo Medical and Dental University in the Department of Biomedical Devices and Instrumentation, and was promoted to Junior Associate Professor in 2014. From 2017 to 2018, he was a visiting researcher at the Departments of Electrical Engineering and Bioengineering at the University of California, Los Angeles (UCLA). His research interests include microfluidics, bio micro-electro-mechanical systems (Bio-MEMS), biosensors, optical systems, and bio-microsystems for medical applications.