Adhesive and Conductive Fibrous Hydrogel Bandages for Effective Peripheral Nerve Regeneration

Peripheral nerve injury is a common disease resulting in reversible and irreversible impairments of motor and sensory functions. In addition to conventional surgical interventions such as nerve grafting and neurorrhaphy, nerve guidance conduits are used to effectively support axonal growth without unexpected neuroma formation. However, there are still challenges to secure tissue-mimetic mechanical and electrophysiological properties of the conduit materials. Herein, the phenylborate-tethered hydrogel-assisted doping effect is elucidated on conductive polymers, enhancing peripheral nerve regeneration when used as a sutureless bandage on the injured nerve. The adhesive and conductive nerve bandage consists of biocompatible hyaluronic acid hydrogel microfibers produced by electrospinning, followed by in situ conductive polypyrrole polymerization on the fibrous mat. Particularly, phenylborate groups enable high adsorption of pyrrole without mechanical crack on the hydrogel network and allow tissue-like stretchability and on-nerve adhesiveness. In a rat crushed nerve injury model, the nerve bandage can effectively promote nerve regeneration through stable sutureless wrapping followed by great electrical transmission on the defect region, showing anatomical and functional recovery of the nerve tissues and preventing muscular atrophy. Such hydrogel fibrous bandages will be a promising surgical dressing to be combined with versatile biomedical devices/materials for peripheral nerve repair.