A Highly-Sensitive Wearable Biosensor Is Set to "Transform" Health Monitoring
Considerably more sensitive than the competition, this new sensor design could help monitor diabetes and blood poisoning.
Researchers from Waseda University, the Beijing Institute of Technology, and the Japan Aerospace Exploration agency have come up with a design for a new, highly-sensitive biosensor — which, the scientists claim, could "transform wearable health monitoring."
"[Our] present telemetry system is robust and tunable," claims project lead Takeo Miyake, professor at Waseda University, of the team's work "It can enhance the sensitivity of sensors to small biological signals. We envision that this technology can be used for developing smart contact lenses to detect tear glucose and/or implantable medical devices to detect lactate for efficient monitoring of diabetes and blood poisoning."
The idea of wearable wireless biosensors isn't new, and commercial versions are already in use in-the-field — but existing models, based on chipless resonant antennas, suffer from low sensitivity. It's this sensitivity issue the team claims to have solved, designing a new bioresonator from a magnetically-coupled reader and a sensor with a high quality factor (Q factor) which easily outperforms the competition.
The team's creation, proven in the lab, uses the reader as an inductor and the sensor as a capacitor parallel-connected to a "chemiresistor" — a variable resistor which changes based on biochemical signals from the wearer, using an enzymatic electrode. Extremely small changes at the electrode are measured by the sensor and amplified by the reader — providing a higher quality signal, and thus greater sensitivity, than has previously been possible.
"The developed amplitude modulation-based PT [Parity-Time]-symmetric bioresonator can detect small biological signals that have been difficult to measure wirelessly until now," Miyake claims. "Moreover, our PT-symmetric system provides two types of readout modes: threshold-based switching and enhanced linear detection. Different readout modes can be used for different sensing ranges."
The team's work has been published in the journal Advanced Materials Technologies under closed-access terms.