Hydrogel-enabled wearable bioelectronics from health monitoring to wound therapy

This review examines hydrogel-enabled wearable bioelectronics across the arc from health monitoring to wound therapy. Hydrogels are valuable in this setting because they combine soft, wet contact, ionic or mixed charge transport, local biochemical exchange, adhesion, therapeutic loading, and excellent biocompatibility within a single wound-facing interface. Their advantage is clearest when monitoring, drug delivery, electrical stimulation, and feedback control must operate on a hydrated, deformable, and contaminated wound surface. Their limitations are equally important: dehydration, swelling, wet-adhesion loss, biofouling, and dose uncertainty can turn material advantages into device failure. While the review draws on the broader health-monitoring literature for transferable design principles, its primary analysis centers on hydrogel interfaces that support wound monitoring, therapy, and closed-loop care. The review compares hydrogels with dry polymer, textile, liquid-metal, and ionogel interfaces; summarizes benchmark-oriented metrics for conductivity, impedance stability, hydration retention, mechanics, adhesion, biosafety, fabrication, and system integration; and uses a three-axis framework to connect composition, charge transport, and therapeutic configuration with translational risk. We argue that hydration-driven interfacial instability is the dominant failure pathway and that future progress depends less on adding functions and more on proving stable, safe, and clinically interpretable performance under wound-relevant conditions.