Application of Hybrid Electrically Conductive Hydrogels Promotes Peripheral Nerve Regeneration

Abstract

Peripheral nerve injury (PNI) occurs frequently, and the prognosis is unsatisfactory. As the gold standard of treatment, autologous nerve grafting has several disadvantages, such as lack of donors and complications. The use of functional biomaterials to simulate the natural microenvironment of the nervous system and the combination of different biomaterials are considered to be encouraging alternative methods for effective tissue regeneration and functional restoration of injured nerves. Considering the inherent presence of an electric field in the nervous system, electrically conductive biomaterials have been used to promote nerve regeneration. Due to their singular physical properties, hydrogels can provide a three-dimensional hydrated network that can be integrated into diverse sizes and shapes and stimulate the natural functions of nerve tissue. Therefore, conductive hydrogels have become the most effective biological material to simulate human nervous tissue’s biological and electrical characteristics. The principal merits of conductive hydrogels include their physical properties and their electrical peculiarities sufficient to effectively transmit electrical signals to cells. This review summarizes the recent applications of conductive hydrogels to enhance peripheral nerve regeneration.

Review on electrically conductive smart nerve guide conduit for peripheral nerve regeneration

“…However, the rate of natural axon growth is relatively slow (1 mm per day), and capacity is limited. 246 In the case of permanent rearrangement of the CNS and PNS circuitry caused by severe injury, most often, the original connectivity cannot be retained. 247,248 Fortunately, nerves are electroactive tissues, and ES has been known for promoting axon growth for a long time.…”

“…Naturally, the axotomy in the peripheral zones contains growth‐programmed genes that can promote regeneration up to specific proximity. However, the rate of natural axon growth is relatively slow (1 mm per day), and capacity is limited 246 …”

From neuromorphic to neurohybrid: transition from the emulation to the integration of neuronal networks

“…To resolve this issue, organic CPs have emerged as ideal candidates for neural interfaces as they meet the mechanical criteria for a soft and biocompatible interface and are also conductive, allowing them to be used as functional elements of soft neural interfaces (figure 3(a)). Among the most frequently used CPs, polyacetylene, polythiophene, poly [3,4-(ethylenedioxy)thiophene] polystyrene sulfonate (PEDOT:PSS), polypyrrole, polyphenylene, and polyaniline have found application in the development of 3D scaffolds for tissue electronics [112,113] or for the development of printed [114] or injectable conductive hydrogels [115], due to the possibility of conjugating biocompatibility, softness and conductivity [116]. For example, 3D scaffolds with nanoelectrodes have been developed for action potential recordings [117][118][119][120] and stimulation [121].…”

Polysaccharide-based nanocomposites for biomedical applications: a critical review

“…For instance, the fabrication of appropriate scaffolds to host stem cells with differentiation capability is in demand. In this regard, polymeric nanocomposites seem to be highly appealing due to their controllable features and electroconductive behaviors 195 (electroconductivity in nerve grafts is important 195 ). Suitable scaffolds should also support cell attachment, differentiation, and growth because they simulate the real extracellular environment, which is required by nerve cells.…”