Flexible, conductive and durable hydrogels based on gluten–poly(vinyl alcohol) complex for electrode patch and wound dressing

Abstract

Wound dressing and electrotherapy are effective approaches for wound repair. However, the electrodes of the electrical stimulation device showed poor conformability with epidermal wound due to the small size and high rigidity. It is urgent to develop a skin adhesive that combines tissue regeneration and conductivity. This study reported a hydrogel dressing with integrated conductive and efficient wound repair function, specifically, curcumin (Cur) and Mg2+ functionalized gluten–poly(vinyl alcohol) (PVA)–glycerol (GPG–Mg–Cur) hydrogel was prepared by freezing and thawing cycles, which was a polymer network structure formed based on the hydrogen bond interaction. The GPG–Mg–Cur hydrogel with an MgCl2 mass ratio of 12.5% exhibited excellent toughness (460 kJ/m3), adhesion strength (18.3 kPa), conductivity (0.58 and 0.52 S/m at room temperature and −20 ℃, respectively), and responded sensitively to 5%–200% strain cycles. Moreover, GPG–Mg–Cur hydrogels showed good conductivity and durability after finger bending, walking, and running movements, and even worked at −20 ℃ and underwater environments. In a mouse model of skin injury, GPG–Mg–Cur hydrogels with sustained-release Cur in situ promoted the proliferation of fibroblasts and showed 91.77% healing rate of wound, providing a regenerative microenvironment for damaged tissues. Overall, this study demonstrates the potential of GPG–Mg–Cur hydrogels as a multifunctional wound dressing that integrates wound repair and assisted electrotherapy.