Development of ecofriendly, biodegradable electrically conductive double-layer bio-hydrogel nanocomposite for sustainable medical device applications

Abstract Electrotherapy devices used for pain relief and muscle recovery often face challenges because traditional electrode materials are not biodegradable, causing environmental issues and being less compatible with the body. While current conductive hydrogels show potential, they usually lack the combination of good electrical performance, biodegradability, and body-friendliness needed for sustainable medical devices. To address these challenges, this study presents a novel, eco-friendly, electrically conductive double-layer nanocomposite bio-hydrogel developed using tragacanth gum (TG) and polyvinyl alcohol (PVA), enhanced with carboxylated graphene (Gr F ) and polypyrrole (PPy). The innovative double-layer design represents a significant advancement over single-layer hydrogels, demonstrating reduced impedance and a substantial increase in conductivity (up to 4.99 × 10⁵ times) at frequencies relevant to electrotherapy applications. Specifically, the tragacanth gum/polyvinyl alcohol/carboxylated graphene@polypyrrole (TPG@PPy) bio-hydrogel exhibited a AC conductivity enhancement of up to 1.5 times compared to the tragacanth gum/polyvinyl alcohol@polypyrrole (TP@PPy) bio-hydrogel at frequency of 80 Hz. Additionally, the material’s high biodegradability, with up to 49% mass loss over 60 days in soil, confirms environmental safety. These results show that the double-layer bio-hydrogel could be a better, eco-friendly option for future electrotherapy devices, making it different from current conductive hydrogels. Graphical Abstract