Neurite Guidance on Laser-Scribed Reduced Graphene Oxide

This paper describes a one-step, chemical-free method to generate micropatterned in vitro neuronal networks on chemically unmodified reduced graphene oxide. The suggested method relies on infrared-based photothermal reduction of graphene oxide, which concurrently leads to the formation of submicrometer-scale surface roughness that promotes neuronal adhesion and guides neurite outgrowth. A commercially available laser source (LightScribe DVD drive) controlled by a computer software can be used to reduce graphene oxide (GO), and its repetitive scribing to a GO film brings about gradual increase and decrease in electrical conductivity and neurite guiding ability of the scribed regions, respectively. Our results also indicate that the observed adhesion-promoting and neurite guiding effect originate from the contrast in surface nanotopography, but not that in conductivity. This method is readily applicable to diverse graphene-based biomedical devices.