A Superabsorbent Chronic Wound Healing Gel Patch with Ultrahigh Ion Conductivity for Electrical Stimulation Therapy

Electrical stimulation (ES) therapy has emerged as a promising therapeutic modality to expedite wound healing, offering a compelling adjunct to traditional wound care. By mimicking the endogenous electric field that naturally facilitates skin regeneration, this approach provides a more efficient and direct method for wound healing therapy compared to conventional treatments such as dressing, compression bandaging, and hyperbaric oxygen therapy. However, conventional stand-alone ES devices, typically based on metal materials, face significant challenges due to mechanical mismatch with the skin, limiting their ability to maintain conformal contact. Additionally, these metal-based stand-alone ES treatment struggle to provide a beneficial antibacterial and anti-inflammatory microenvironment, thereby restricting their overall healing efficacy. In response to these limitations, there has been a growing interest in developing soft conductors based on hydrogels for ES therapy. Hydrogels, with their high water content and superior ionic conductivity, present a promising alternative. Despite these advantages, hydrogels face a critical limitation in bioelectronics due to their dehydration, ultimately challenging their long-term stability and functional reliability.<br/> Here, we propose a biocompatible ion conductor, based on a hydration gel wound dressing composed of a choline-based ionic liquid (IL) embedded in a gelatin matrix, which maintains a moist, antibacterial environment with high ion conductivity to accelerate tissue regeneration through exogenous ES. This hydrophilic IL with low vapor pressure hydrates by water, which are retained within the gelatin's triple-helix structure, resulting in high ion and water content without dehydration. In addition, this IL-water interaction dissociates ion pairs into free ions, significantly increasing ion conductivity compared to conventional iongels. The resulting hydration gel, with its high water content, possesses a low Young's modulus similar to human skin. Furthermore, the intrinsic Arg-Gly-Asp (RGD) sequence in the gelatin enhances cell adhesion, mobility, and proliferation, promoting adhesion and conformal contact with the skin. Consequently, we have developed a soft(~70kPa), anti-dehydration(over 1 year), and highly ion-conductive(&gt;30ms/cm) ES patch that effectively promotes wound regeneration. We believe our long-term stable hydration gel serves as a blueprint for developing the next-generation wound healing management system.