Sustainable and High-Performance Silk Fibroin Ionogels for Next-Generation Wearable Bioelectronics and Athletic Training

The integration of advanced biomaterials into wearable electronics is crucial for the development of next-generation epidermal sensors. Here, we present a calcium-modified silk fibroin (Ca@SF) ionogel that addresses key limitations of conventional epidermal sensors by leveraging metal chelation and water-trapping mechanisms to enhance adhesion, stretchability, and electrochemical performance. The Ca@SF ionogel exhibits outstanding mechanical flexibility, with an elongation capability of up to 704%, and strong adhesion (23.7 kPa on porcine skin), ensuring stable skin–electrode interfaces for real-time physiological monitoring. We demonstrate its applicability in sports biomechanics through strain-sensing capabilities for monitoring joint kinematics during basketball shooting, enabling precise posture correction and training optimization. Furthermore, the Ca@SF-based electrode significantly outperforms conventional Ag/AgCl electrodes in electrocardiogram monitoring, providing superior signal fidelity and long-term stability for postexercise recovery assessments. Notably, the ionogel is fully recyclable, offering a sustainable alternative to conventional electronic materials. This study highlights the multifunctionality of Ca@SF ionogels and their potential to revolutionize wearable bioelectronics in sports science, rehabilitation, and personalized healthcare.