Recyclable and Degradable MXene-Based Conductive Hydrogels for Sustainable Multimodal Motion and Health Monitoring

Conductive hydrogels are widely recognized for their flexibility and biocompatibility, making them ideal for soft electronics and health monitoring. However, due to the lack of recyclability of current hydrogel materials, environmental problems arise, thereby restricting the application of sensors. This study, through the integration of oxidized starch, gelatin, mesoporous glass nanoparticles (MBGNs), and MXene materials, developed a recyclable and degradable GOMM hydrogel material, which, when successfully built, could be used for exercise and a variety of physiological health flexible wearable sensors. This hydrogel, formed through noncovalent cross-linking (hydrogen bonds and Schiff base bonds), demonstrates excellent adhesion (53.49 kPa on pig skin). The high electrical conductivity of MXene endowed the GOMM hydrogel with excellent electrical conductivity (5.05 mS/cm). Moreover, the existence of MBGNs provides a large number of cross-linking points for hydrogels, which further optimizes the mechanical properties of hydrogels (247.22%). Notably, the hydrogel degrades in phosphate-buffered salinle solution within 24 days (the degradation rate reaches 92%), addressing electronic waste concerns. Based on the above excellent performance, when assembled into wearable sensors, it can achieve multiscenario applications (strain, temperature, humidity, electromyogram, and electrocardiogram signals) and health monitoring. Furthermore, the hydrogel is recyclable and can be thermally reprocessed, offering an ecofriendly solution for next-generation soft electronics in medical diagnostics and wearable technologies.