A multifunctional conductive organohydrogel as a flexible sensor for synchronous real-time monitoring of traumatic wounds and pro-healing process

Abstract

Ion-conductive hydrogels (ICHs) offer promising applications in the realm of flexible bioelectronics due to their attributes, such as transparency, flexibility, tissue adhesion, and self-healing. However, it remains a challenge to integrate excellent material properties and bio-properties into ICHs-based smart wearables for intricate biomedical applications. Herein, a multifunctional conductive C-CST/PMC organohydrogel with stretchability, anti-freezing, self-healing, antibacterial, antioxidant, and biocompatibility was synthesized by catechol-conjugated chitosan (C-CS), silk nanofibrils (SNFs), tannic acid (TA), MgCl2/CaCl2, and polyvinyl alcohol (PVA), with a binary solvent system composed of ethylene glycol (EG) and H2O. The C-CST/PMC exhibited excellent mechanical properties (175 kPa stress and 330 % strain), anti-freezing capacity, moisture retention, self-healing performance, and high conductivity (1.76 mS/cm at 25 °C and 1.43 mS/cm at –18 °C). Moreover, we have employed this organohydrogel as a flexible strain sensor for monitoring human movements, achieving a high sensitivity (gauge factor (GF) = 1.20 at 100 % strain) and glorious fatigue resistance (>1000 cycles). Furthermore, the C-CST/PMC displayed good antibacterial, antioxidant, hemo-, and cytocompatibility. In vivo tests on diabetic rats have demonstrated that the C-CST/PMC organohydrogel effectively reduces inflammatory responses and promotes angiogenesis, consequently expediting wound healing. Notably, trials involving the use of this flexible sensor in a medical silicone bionic shoulder have indicated its potential as a wearable electronic device for real-time monitoring of human wound healing progress. Overall, this research contributes novel insights to the design and fabrication of multifunctional flexible sensors that synchronous pro-healing and real-time monitoring of traumatic skin.