In Situ Synthesis of Robust Conductive Cellulose/Polypyrrole Composite Aerogels and Their Potential Application in Nerve Regeneration

Abstract

Nanostructured conductive polymers can offer analogous environments for extracellular matrix and induce cellular responses by electric stimulation, however, such materials often lack mechanical strength and tend to collapse under small stresses. We prepared electrically conductive nanoporous materials by coating nanoporous cellulose gels (NCG) with polypyrrole (PPy) nanoparticles, which were synthesized in situ from pyrrole monomers supplied as vapor. The resulting NCG/PPy composite hydrogels were converted to aerogels by drying with supercritical CO2, giving a density of 0.41-0.53 g cm(-3), nitrogen adsorption surface areas of 264-303 m(2) g(-1), and high mechanical strength. The NCG/PPy composite hydrogels exhibited an electrical conductivity of up to 0.08 S cm(-1). In vitro studies showed that the incorporation of PPy into an NCG enhances the adhesion and proliferation of PC12 cells. Electrical stimulation demonstrated that PC12 cells attached and extended longer neurites when cultured on NCG/PPy composite gels with DBSA dopant. These materials are promising candidates for applications in nerve regeneration, carbon capture, catalyst supports, and many others.

Optimal electrical stimulation boosts stem cell therapy in nerve regeneration

“…While conductive conduits have shown the ability to induce neuronal differentiation of PC12 cells in vivo [52] and promoting sciatic nerve regeneration in rat models by transmitting self- originated electrical stimulation between cells [53], in our study, we used external electrical stimulation on transplanted NCSCs to promote the Schwann cell differentiation and nerve regeneration. The polycaprolactone nanofiber we used is not a conductive material; however, the hydrogel + PBS filling is.…”

One-pot solvent exchange preparation of non-swellable, thermoplastic, stretchable and adhesive supramolecular hydrogels based on dual synergistic physical crosslinking

“…To improve the mechanical properties of chemically crosslinked hydrogels, researchers have developed ingenious strategies, including nanocomposite hydrogels, double-network hydrogels, hybrid crosslinking hydrogels and tetra-polyethylene glycol hydrogels. [14][15][16][17][18][19][20][21][22] Recently, increasing research attention has been dedicated to enhancing the mechanical performance of physically crosslinked supramolecular hydrogels. One recent study demonstrated very tough physical hydrogels composed of polyampholytes.…”

Incorporation of Conductive Materials into Hydrogels for Tissue Engineering Applications

“…Therefore, the conductive hydrogel can provide an electrically efficient and adjustable cell growth platform. In addition, CNTs can be applied to electron-emitting fibrous polymers to improve mechanical strength [165]. Shin et al synthesized functional cardiac patches by seeding neonatal rat cardiomyocytes on CNT-incorporated photo crosslinkable gelatin methacrylate (GelMA) hydrogels (Figure 15) [166].…”