Amperometric glucose biosensors based on integration of glucose oxidase onto Prussian blue/carbon nanotubes nanocomposite electrodes

Nanosized Prussian blue (PB) particles were synthesized with a chemical reduction method and then the PB nanoparticles were assembled on the surface of multiwall carbon nanotubes modified glassy carbon electrode (PB/MWNTs/GCE). The results showed that the PB/MWNTs nanocomposite exhibits a remarkably improved catalytic activity towards the reduction of hydrogen peroxide. Glucose oxidase (GOD) was immobilized on the PB/MWNTs platform by an electrochemically polymerized o-phenylenediamine (OPD) film to construct an amperometric glucose biosensor. The biosensor exhibited a wide linear response up to 8 mM with a low detection limit of 12.7 mu M (S/N = 3). The Michaelis-Menten constant K-m and the maximum current i(max) of the biosensor were 18.0 mM and 4.68 mu A, respectively. The selectivity and stability of the biosensor were also investigated.