A novel nerve guide conduit applied with conductive polymer PEDOT: PSS for repair of long sciatic nerve gap

Despite that artificial nerve guide conduits (NGC) have been widely applied in nerve tissue repair for treating peripheral nerve injury (PNI), those apparatuses face great challenges in repairing long-gap nerve defects due to their non-conductive nature. Herein, we report that such clinical issue can be addressed by a bio-mimic polycaprolactone (PCL)-based nerve conduit doped with conductive mixtures (denoted as PP) of polyethylene dioxythiophene (PEDOT) and polystyrene sulfonate (PSS). The PCL-PP nerve conduits demonstrated porous reticular fibrous networks with biocompatible and physicochemical properties. The structure novelty endows the material with a robust mechanical character with a Young’s modulus of 0.32 MPa and a tensile strength of 2.9 MPa. Benefited from the capability of conducting endogenous electrical stimulation due to the high conductivity of 5.8 × 10 -3 S/m, the PCL-PP nerve conduits can regulate the biological behavior of Schwann cells (SCs), and remarkably promote the myelin sheath growth and regeneration of nerve tissues in a 10 mm sciatic nerve defect SD rat model. Compared to the contrast nerve conduits without PP compositions, the PCL-PP nerve conduits accelerated the recovery rate of extremity motor function of SD rats by a factor of 1.25-fold. These findings prove that our reported novel PCL-PP composite nerve conduit with functional integration of bioelectrical stimulation is a promising therapeutic approach toward PNI therapy.