Biomimetic Choline-Like Graphene Oxide Composites for Neurite Sprouting and Outgrowth

Abstract

Neurodegenerative diseases or acute injuries of the nervous system always lead to neuron loss and neurite damage. Thus, the development of effective methods to repair these damaged neurons is necessary. The construction of biomimetic materials with specific physicochemical properties is a promising solution to induce neurite sprouting and guide the regenerating nerve. Herein, we present a simple method for constructing biomimetic graphene oxide (GO) composites by covalently bonding an acetylcholine-like unit (dimethylaminoethyl methacrylate, DMAEMA) or phosphorylcholine-like unit (2-methacryloyloxyethyl phosphorylcholine, MPC) onto GO surfaces to enhance neurite sprouting and outgrowth. The resulting GO composites were characterized by Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, UV-vis spectrometry, scanning electron microscopy, and contact angle analyses. Primary rat hippocampal neurons were used to investigate nerve cell adhesion, spreading, and proliferation on these biomimetic GO composites. GO-DMAEMA and GO-MPC composites provide the desired biomimetic properties for superior biocompatibility without affecting cell viability. At 2 to 7 days after cell seeding was performed, the number of neurites and average neurite length on GO-DMAEMA and GO-MPC composites were significantly enhanced compared with the control GO. In addition, analysis of growth-associate protein-43 (GAP-43) by Western blot showed that GAP-43 expression was greatly improved in biomimetic GO composite groups compared to GO groups, which might promote neurite sprouting and outgrowth. All the results demonstrate the potential of DMAEMA- and MPC-modified GO composites as biomimetic materials for neural interfacing and provide basic information for future biomedical applications of graphene oxide.

Graphene-based materials for tissue engineering

“…GO can be functionalized with different functional groups such as amino-, sulfonic acid-, or methoxyl-groups [113]. In addition, biomimetic acetylcholine- and phosphorylcholine-like units such as dimethylaminoethyl methacrylate (DMAEMA) and 2-methacryloyloxyethyl phosphorylcholine (MPC) can be immobilized on the GO surface [114]. Therefore, neurite extension and the number of neuronal branches could be regulated by these functional groups on the GO substrate, especially on DMAEMA-bound GO.…”

In Vitro Evaluation of Biocompatibility of Uncoated Thermally Reduced Graphene and Carbon Nanotube-Loaded PVDF Membranes with Adult Neural Stem Cell-Derived Neurons and Glia

“…In these previous studies, cells were either seeded on graphene or on GBNs coated with proteins such as laminin and synthetic polymers such as poly-lysine, substances which are known to promote cell adhesion and neurite outgrowth (Vicario et al, 1993; Calof et al, 1994; Otaegi et al, 2007; Nishimune et al, 2008). In addition, cells were plated on graphene composites, graphene oxides, or on reduced graphene oxides with different surface charges and degree of electrical, photo, and laser stimulation (Akhavan and Ghaderi, 2013a,b, 2014; Tu et al, 2013a, 2014; Akhavan et al, 2014, 2015; Guo et al, 2016a). Similarly, both uncoated and coated functionalized single-walled CNTs (SWCNTs) and multi-walled CNTs (MWCNTs) as well as aligned CNTs and nanofibers have been reported to permit and stimulate neuronal growth and the formation of active synaptic contacts (Jan and Kotov, 2007; Malarkey et al, 2009; Cellot et al, 2011; Jin et al, 2011; Fabbro et al, 2013; Gupta et al, 2015; Vicentini et al, 2015).…”

Multivalent Interactions between 2D Nanomaterials and Biointerfaces

“…Both biomimetic choline‐like GO composites were able to enhance the primary rat hippocampal neurite sprouting and outgrowth significantly more than unmodified GO. However, GO‐DMAEMA was even more efficient than GO‐MPC …”