Magnetic Nanoparticle-Reduced Graphene Oxide Nanocomposite as a Novel Bioelectrode for Mediatorless-Membraneless Glucose Enzymatic Biofuel Cells.

In this work, an enzymatic biofuel cell (EBC) based on a membraneless and mediatorless glucose enzymatic fuel cell system was constructed for operation in physiological conditions (pH 7.0 and temperature 37 °C). The new platform EBC made of nanocomposite, including magnetic nanoparticles (FeO NPs) and reduced graphene oxide (RGO), was used for the immobilization of glucose oxidase (GOD) as bioanode and bilirubin oxidase (BOD) as biocathode. The EBC bioelectrodes were fabricated without binder or adhesive agents for immobilized enzyme and the first EBC using superparamagnetic properties with FeO NPs has been reported. The performance of the EBC was evaluated with promising results. In EBC tests, the maximum power density of the EBC was 73.7 μW cm and an open circuit voltage (OCV) as +0.63 V with 5 mM of glucose concentration for the physiological condition of humans. The FeO-RGO nanocomposite offers remarkable enhancement in large surface areas, is a favorable environment for enzyme immobilization, and facilitates electron transfer between enzymes and electrode surfaces. FeO and RGO have been implied as new promising composite nanomaterials for immobilizing enzymes and efficient platforms due to their superparamagnetism properties. Thus, glucose EBCs could potentially be used as self-powered biosensors or electric power sources for biomedical device applications.