Graphene Biosensor as Affinity Biosensors for Biorecognition between Guanine Riboswitch and Ligand

•G-FET biosensor was developed to detect the binding interactions between GR and ligand molecules.•Mechanisms for electric-neutral molecule sensing was revealed by molecular dynamics simulation.•Equilibrium dissociation constants KD and binding free energy ΔG of GR and ligand molecules were obtained.