Multilayer Janus-based printed flexible electrodes with broad bioelectrical compatibility for multi-modal health monitoring

Abstract

Flexible bioelectronic systems have shown great potential for continuous physiological monitoring, yet signal instability and insufficient multimodal coordination under dynamic conditions remain key challenges. Here, we report a Janus Flexible Electrode System (JFES) integrating printed Ag/PEDOT composite electrodes, electrospun thermoplastic polyurethane (TPU) membranes, and an elastomeric adhesive interlayer for simultaneous acquisition of electrophysiological and strain signals. Benefiting from the dual-surface functional partitioning and stress-buffered multilayer structure, the device exhibits excellent flexibility, strong skin adhesion, stable electrical performance, and a high EMG signal-to-noise ratio of approximately 36 dB. Through feature-level EMG–strain fusion assisted by a lightweight convolutional neural network (CNN), the system achieves a gesture-recognition accuracy of 94.34%, outperforming the EMG-only model. Furthermore, in vivo experiments on anesthetized mice demonstrate the system's capability for synchronous recording of tail-pinch-associated cortical potentials and strain responses. Quantitative ECoG analysis shows stimulation-induced redistribution of spectral power within 0.5–30 Hz, while the strain channel captures corresponding mechanical responses. This study provides a scalable and reliable Janus electrode strategy for multimodal bioelectronic interfaces, bridging electrophysiological and mechanical signal monitoring toward intelligent health diagnostics and neurophysiological applications.