Advances in Flexible Electronic Systems for Electrical Stimulation Assisted Wound Healing

Progress in miniaturization techniques coupled with advancements in material science and wearable technologies has transformed electrical stimulation (ES) technique of wound healing into a smart stand-alone patch. The present review article begins with a glimpse of the market demand and need for ES followed by a brief highlight on wound healing stages and the effects of ES in them. Thereafter, a roadmap on the use and effects of different ES modes is provided covering trials over in vitro cell-culture models as well as in vivo animal models along with details of ES safety parameters and biomaterial interface challenges. Following this, the article provides a detailed description of various inorganic flexible electronic-based ES patches for accelerated wound healing developed during the last decade along with an exhaustive study on various wound monitoring sensors like pH, temperature, moisture, bacterial infection, and metabolites, as well as their interdependency in influencing overall wound health and healing status. Additionally, the article also presents a brief insight into modern ES patches categorized under self-powered nanogenerator-driven and hydrogel-based patches along with integration of wireless communication and closed-loop control systems for an efficient wound healing system. Finally, the article concludes with a brief note highlighting the current unresolved bottlenecks required for its wider acceptance as well as the future attributes of ES patches catering the needs of generic to complex, hard-to-heal wounds with sophisticated multiparameter monitoring units and integrated AI/ML-driven solutions for driving the next-generation smart bandages.