Controlled chitosan coated Prussian blue nanoparticles with the mixture of graphene nanosheets and carbon nanoshperes as a redox mediator for the electrochemical oxidation of nitrite

The graphene nanosheets and carbon nanospheres mixture (GNS-CNS) was prepared by electrolyzing graphite rob in KNO3 solution under a constant current. The cationic chitosan (CS) coated Prussian blue (PB) as an efficient redox mediator could interact with the anion GNS-CNS via electrostatic interaction. The synergy effect of CS@PB nanoparticles and GNS-CNS contributed to the excellent electrochemical response towards the nitrite oxidation. The as-prepared CS@PB/GNS-CNS modified glass carbon (GC) electrode demonstrated its high sensitivity, low detection limit, short response time, and wide concentration range for the nitrite detection. (C) 2011 Elsevier B.V. All rights reserved.