Lithography-free fabrication of bistability graphene FET biosensor

A novel non-lithographic, contamination-free technique for the fabrication of graphene field effect transistors (GFET) is presented. The GFET was modified with C reactive protein aptamer. Iron nanoparticles were immobilized on the GFET channel surface by using an aptamer-target protein (CRP)-aptamer sandwich method. Bistability signal was obtained by backgate voltage up/down sweeping. The bistability phenomenon caused by the target protein induced NPs adsorption demonstrates a novel high sensitive biosensing method.