Eel-Inspired Self-Powered Hydrogel Nerve Conduit: A Fully Degradable Scaffold for Peripheral Nerve Repair

Electrical stimulation effectively promotes nerve regeneration and functional recovery, but its clinical application faces challenges such as energy supply limitations, long-term stability issues, and implantation safety concerns. Inspired by the bioelectrogenic mechanism of electric eels, this study developed an electric-eel-inspired ionogel battery (EE-iHB) using chitosan (CS), chondroitin sulfate (CSA), and hydroxyethyl cellulose (HEC). The battery exhibits not only excellent biocompatibility but also outstanding ionic conductivity. By mimicking the intricate multilayer structure of electric eel electrocytes and employing a layer-by-layer self-assembly technique, synergistic optimization of mechanical properties and electrical conductivity was achieved in the nerve conduit. In vitro experiments confirmed the stable and continuous generation of bioelectrical signals. In vivo studies using a rat sciatic nerve injury model demonstrated that the experimental group implanted with this novel conduit showed superior nerve regeneration speed and functional recovery compared to conventional nerve conduits. Histological and electrophysiological analyses further verified that the weak current generated by the battery effectively activation of Schwann cells, guides orderly axonal growth, and promotes myelination. The use of flexible gel materials ensures seamless integration with neural tissues, guaranteeing both safety and long-term reliability in neural repair applications.