Abstract: In recent years, electrically conductive hydrogel-based nerve guidance conduits (NGCs) have yielded promising results for treating peripheral nerve injuries (PNIs). However, developed ones are generally pre-manufactured and exhibit a limited ability to achieve good contact with nerve tissue with irregular surfaces. Herein, we developed a plasticine-like electrically conductive hydrogel consisting of gelatin, conducting polypyrrole, and tannic acid (named GPT) and assessed its ability to promote peripheral nerve regeneration. The shape-persistent GPT hydrogel exhibited good self-healing properties and could easily be molded to form a conduit that could match any injured nerve tissue. Their electrical properties could be tuned by changing the PPy concentration. In vitro, the improved conductivity of the hydrogel promoted dorsal root ganglion (DRG) axonal extension. More importantly, we found that the GPT hydrogel enhanced axonal regeneration and remyelination in vivo, preventing denervation atrophy and enhancing functional recovery in a mice model of sciatic nerve injury. These results suggest that our plasticine-like NGC has huge prospects for clinical application in the repair of PNI.

Key words: Plasticine-like, Conductive hydrogel, Self-healing, Moldability, Peripheral nerve conduit