Accelerated Outgrowth of Neurites on Graphene Oxide-Based Hybrid Electrospun Fibro-Porous Polymeric Substrates

Abstract

Fabrication of a surface-engineered electrospun scaffold having biomimetic properties like the extracellular matrix (ECM) is essential for neural tissue engineering. An electroconductive and elastomeric scaffold with aligned fibers acting as a substrate may have a great impact on the directional outgrowth of neurites. In this study, we have electrospun electrically conductive, polyurethane-based elastomeric and topographically aligned fibro-porous neural scaffolds. Adhesive proteins of the ECM are documented to have an important role in controlling neuronal cell behavior, including cell adhesion, proliferation, and neurite outgrowth. These bio-adhesion proteins or nanomaterials mimicking their action, if used for surface modification of neural scaffolds, may have the potential to accelerate the nerve repair process. Thus, electrospun scaffolds fabricated were surface-engineered using a unique and modified single-step electrospraying technique to coat the scaffold surface with an exploratory bio-adhesion agent, a thin layer of graphene oxide (GO) films. The study was then carried out to determine if the GO-coated electrospun electroconductive polycarbonate urethane (PCU) substrate can improve the bio-interface attributes of these scaffolds or may alter the neurite outgrowth of PC-12 cells like any other bio-adhesion proteins. Therefore, the hybrid scaffolds with GO coatings were compared with similar scaffolds coated with poly-l-lysine (PLL) for neural cell adhesion, proliferation, and neurite extension. Neurite outgrowth studies showed that although the average neurite length was comparable on both GO- and PLL-coated surfaces, the length profile of neurites, when categorized based on length, showed an increased number of lengthier neurites on the GO-coated hybrid scaffolds. In particular, the study brings out an innovative surface engineering technique for the coating of GO on polymeric scaffolds. It may be further put together in designing of hybrid surfaces with nanotopographical biophysical cues on three-dimensional neural scaffolds, which in turn may stimulate an accelerated neuronal regeneration via providing an enhanced ECM like milieu.

Collagen/chitosan-functionalized graphene oxide hydrogel provide a 3D matrix for neural stem/precursor cells survival, adhesion, infiltration and migration

“…Moreover, Col/CSGO nanocomposite permits neurite branches and outgrowth of NS/PCs (Figure 9). These results are in consistent with those reported by Thampi et al, 64 in which GO thin films enhanced neurite extensions.…”

“…Furthermore, GO can provide not only a micro/nanostructure but also a unique physicochemical cue for the better cell material interface that induce cellular interaction. 59,64 NS/PCs are sensitive to nanostructured substrates and nano-scale features would increase protein attachment and cell adhesion. The results of the cells SEM images indicated that in the three-dimensional Col scaffold more cells were spherical and a few cells appeared with neurite outgrowth (Figure 9).…”

Biomedical Applications of Electrospun Graphene Oxide

“…Here it was shown that neurite outgrowth of PC-12 cells presented superior results when in contact with the GO-coated PCU material in comparison to poly- l -lysine (PLL) coated material. It was revealed that while the mean neurite length was similar on both GO and PLL-coated surfaces, the profile of length of neurites, when classified by length, showed more lengthier neurites on the GO-coated scaffolds . This study presents a novel surface engineering technique for GO coating on polymeric material.…”

“…Release of drug properties showed that the π–π stacking interaction between the TCH drug and GO improved the controlled release of TCH compared to control groups without GO present. An electrospun GO/polycarbonate urethane (PCU) scaffold has been studied for its use in neural tissue engineering applications . Here it was shown that neurite outgrowth of PC-12 cells presented superior results when in contact with the GO-coated PCU material in comparison to poly- l -lysine (PLL) coated material.…”

“…This study presents a novel surface engineering technique for GO coating on polymeric material. This novel material may be used as a three-dimensional neural scaffold which can stimulate accelerated neuronal regeneration by contributing an upgraded ECM-like climate …”