Graphene Nanonet for Biological Sensor

Graphene nanoribbons (GNRs) have been drawing attentions because they exhibited improved transconductances compared with graphene, and their edges could be functionalized with various chemicals or biological molecules. Herein, we developed a facile method to fabricate graphene nanonet (GNN) patterns over a large surface area for biological applications. In this method, the networks of V$_{2}$O$_{5}$ nanowires were adsorbed selectively in the desired regions on a graphene layer, and they were utilized as a shadow mask during the reactive ion etching on the graphene layer. This fabrication process allowed us to prepare large scale patterns of GNN structures which were comprised the continuous networks of GNRs with chemical functional groups on their edges. The chemical functional groups in the GNN could be functionalized with biological molecules such as DNAs for biological applications. Using the GNN-based biochip devices, we have successfully achieved the fluorescence imaging of DNAs on the GNN channels and the electrical detection of the DNAs at 1nM concentrations. Our method could be a powerful strategy to mass-produce GNR-based devices and should enable various practical bio-applications.