Advanced Janus Electrode and Nanomesh Strain Sensor for Robust, Long-Term Biosignal Monitoring

Accurate, long-term monitoring of biosignals under dynamic conditions, such as sweating and skin deformation, is critical for wearable healthcare devices. In this presentation, we introduce two cutting-edge technologies designed for continuous and stable biosignal monitoring on the skin. The first is a Janus electrode with stable asymmetric wettability, composed of an ultrathin hydrophobic Au membrane and water-durable hydrophilic nanofiber layers. This electrode exhibits high breathability, conformability, and unidirectional sweat transport, maintaining dry skin-electrode contact for up to 7 days, even during physical activity. The second innovation is an ultrasoft nanomesh strain sensor, which is mechanically compliant and highly durable against friction. With a tensile stiffness lower than that of the skin and extreme durability under pressures exceeding 160 kPa, the sensor accurately tracks skin deformations, even during intense activities. Recent advancements include improved adhesion properties for enhanced conformal contact, increased environmental stability across various humidity and temperature ranges, and extended durability in challenging conditions. These technologies demonstrate significant potential for real-time, continuous monitoring of physiological signals in real-world environments, including daily activities and exercise, paving the way for next-generation wearable health monitoring systems.