Water-resistant and underwater adhesive ion-conducting gel for motion-robust bioelectric monitoring

Bio-adhesive and ion-conductive hydrogels are of great significance in the field of bioelectric monitoring, but many challenges remain for practical applications in complex conditions and underwater environments. Here, we report a bioelectrical electrode based on ion-conductive gel with excellent water-resistant, underwater adhesion, and swelling resistance for application in the aquatic environment. Especially, the gel electrode exhibits extremely low impedance (<10 Ω) at physiologically relevant frequencies, long-term electrical and structural stability in the aqueous environment. The static noise (19 uV) and dynamic noise (30 uV) it generating are much lower than the current bioelectrodes and commercial gel electrodes. It can effectively reduce the influence of motion artifacts and obtain real-time high-quality electrocardiogram and electromyography signals underwater. Therefore, it shows great potential in long-term motion-robust underwater bioelectric monitoring.