Highly stretchable and conductive liquid metal-based multifunctional organohydrogel for behavior monitoring and chronic diabetic wounds treatment

Diabetic wounds are one of the most serious complications of diabetes mellitus caused by impaired blood vessel formation, nerve damage, excessive inflammation, hypoxia, and persistent infections, which severely affects the quality of life of patients. Conductive hydrogel-based flexible epidermal sensors have great potential for personal medical monitoring and diabetic chronic wound therapy. Combining electrical stimulation (ES) therapy with motor activity monitoring can guide clinical practice and thus radically improve treatment outcomes. In this study, a multifunctional conductive Gel-TBA-LM organohydrogel flexible sensor with antimicrobial, antioxidant, and biocompatible properties was synthesized using gelatin (Gel) and 2,3,4-trihydroxybenzaldehyde (TBA) as the substrates, and liquid metal (LM) as the functional filler. Its mechanical properties and frost resistance were enhanced by the Hofmeister effect and solvent substitution strategy. The Gel-TBA-LM organohydrogel has excellent mechanical properties (1.2 MPa modulus and 400 % strain) and high electrical conductivity (673.76 S/m). The corresponding measurement factor (GF) values were 0.26 (0-50%) and 2.88 (50-200%) at 0-200% strain, thus can sensitively and accurately detect movement behavior of different joints. In addition, the combination of Gel-TBA-LM organohydrogel with ES promotes diabetic wound healing by coordinating angiogenesis and macrophage M2-type polarization through the VEGF/ERK pathway while maintaining vascular cell-neuronal cell intercellular crosstalk. This study provides a valuable reference for the development of multifunctional conductive organohydrogel sensors for chronic diabetic wound repair and personal health monitoring. Schematic diagram of Gel-TBA-LM organohydrogel integrating motion sensing and therapeutic functions. In this study, based on the Schiff base, coordination bond and hydrogen bond forces between gelatin (Gel), 2,3,4-trihydroxybenzaldehyde (TBA) and liquid metal (LM), multi-functional Gel-TBA-LM conductive organohydrogels were prepared by using Hofmeister effect and solvent substitution strategy. Gel-TBA-LM organohydrogel has good mechanical, conductive, antioxidant, antibacterial and antifreezing properties, and can detect mechanical transmission signals from the human body. In addition, synergistic electrical stimulation (ES) can coordinate angiogenesis and M2 polarization of macrophages through the VEGF/ERK pathway, while maintaining cell to cell tandem between vascular cells and neurons, thus promoting wound healing in diabetes patients. • Hofmeister effect and solvent substitution yield highly stretchable and antifreeze Gel-TBA-LM organohydrogel. • TBA endows Gel-TBA-LM organohydrogel with antibacterial, anti-inflammatory, and antioxidant properties. • Gel-TBA-LM organohydrogel containing LM can serve as wearable sensors for monitoring human motion. • Gel-TBA-LM organohydrogel combined with ES accelerates diabetic wound healing through the VEGF/ERK pathway.