Graphene-based electrochemical biosensor for pathogenic virus detection

Abstract

A graphene based biosensor system is presented for performing highly sensitive pathogenic virus detection. A free-standing conductive graphene film was prepared as a novel electrochemical sensor through two steps: synthesis of a graphene oxide (GO) film from GO colloidal suspensions by using a speed vacuum concentrator and thermal annealing process at 900°C with H2/Ar flow to generate a reduced GO film. The resultant graphene film shows an excellent electron transfer property on the surface in the [Fe(CN)6]3−/4− redox system and is used as a working electrode in the electrochemical biosensor. The surface of graphene is modified with pyrene derivatives, and then covalently linked with virus-specific antibodies. The target cell, rotavirus, is captured on the graphene film through antibody-antigen interaction, and the entire process was monitored by cyclic voltammetric responses. A 105 pfu/mL of input cells is detected with ca. 30.7% sensitivity, and ca. 1.3% sensitivity is measured with 103 pfu/mL of input cells, demonstrating that graphene film based electrode can be applied for electrochemical biosensor.