Topological Supramolecular Network-Enabled PEDOT:PSS Hydrogel Sensor for High-Sensitivity Strain Monitoring and EMG/ECG Bioelectronic Sensing

Stretchable conductive hydrogels have emerged as ideal interfaces for seamless and biocompatible integration with human skin, showing significant potential in medical electronic applications. However, achieving a balance between high mechanical robustness and excellent electrical conductivity remains challenging, particularly for electromyography (EMG) and electrocardiography (ECG) sensing. Here, a high-performance conductive hydrogel sensor is fabricated by incorporating a mechanically interlocked polyrotaxane into a topological network. The resulting hydrogel exhibits a remarkable combination of properties: ultrahigh stretchability (2488%), high electrical conductivity (5.1 S/m), tissue-like strength (65 kPa), and suitable skin adhesion (38 kPa). Notably, high conductivity is achieved with only a trace amount of PEDOT:PSS (0.08 wt %). The hydrogel also demonstrates significant antibacterial activity, highlighting its potential for bioelectronic applications. Fabricated wearable sensors show high sensitivity (gauge factor of 5.7) and fast response (100 ms). They are successfully applied not only in monitoring vigorous human motions but also in real-time ECG and EMG signal acquisition, outperforming commercial sensing gels with superior signal-to-noise ratio.