Development of Dual-Functional Hydrogel-Based Conductive Electrodes for Accelerated Wound Healing and Motion Sensing

Flexible conductive hydrogel-based electrodes are promising for biomedical use, combining enhanced wound healing, bioelectrical signaling, and real-time motion sensing, with broad potential in personalized medicine, wearable electronics, and smart prosthetics. In this study, electrically conductive hydrogels with dual functionality were developed for accelerated wound healing and motion sensing applications. The hydrogel electrodes were synthesized via a freeze-thaw cross-linking method using polyvinyl alcohol (PVA), crystalline nanocellulose (CNC), Laponite (LAP), and polyaniline (PANI). The influence of CNC and LAP content on the electrical conductivity, mechanical strength, swelling capacity, and degradation behavior of the hydrogels was systematically investigated. The PVA-CNC-LAP/PANI hydrogel optimized for electrical conductivity (1.5 wt.% CNC and 1.25 wt.% LAP) demonstrated outstanding multifunctional performance, combining robust mechanical strength (490 kPa tensile strength, 2.57 mm/mm elongation, 162 kPa elastic modulus, and 656 kJ/m³ toughness) with excellent electrical properties, including high conductivity (33.65 S/m), reliable sensitivity (gauge factor = 1.74), and remarkable durability (>500 cycles at 20% strain). Biocompatibility and cell migration potential of this hydrogel electrode were assessed through scratch assays using human dermal fibroblasts (HDF). Additionally, the hydrogel's performance was evaluated in flexible sensor, smart finger actuator, and electrocardiogram (ECG) electrode applications. The biocompatible PVA/CNC/PANI-LAP hydrogel electrodes exhibited satisfactory electrical conductivity, excellent mechanical integrity, and electroresponsive behavior, thereby effectively supporting HDF proliferation, directed migration, and motion detection capabilities.