Electrochemical Immobilization of Osmium Complex onto the Carbon Nano-Tube Electrodes and its Application for Glucose sensor

Abstract

The multi-wall carbon nano-tube composite mixed with carbon paste electrode presented more sensitive and selective amperometric signals in the oxidation of glucose than general screen-printed carbon electrodes(SPCEs). Redox mediators to transport electrodes from enzyme to electrodes are very important part in the biosensor. A novel osmium redox complex was synthesized by the coordinating pyridine group containing primary amines which were electrochemically immobilized onto the MWCNT-SPCEs surface. Electrochemical studies of osmium complexes were investigated by cyclic voltammetry, chronoamperometry. The surface coverage of osmium complexes on the modified carbon nano-tube electrodes were significantly increased at 100 time (Gamma(0) = 2.0 x 10(-9) moles/cm(2)) compared to that of the unmodified carbon electrodes. It's practical application of the glucose biosensor demonstrated that it shows good linear response to the glucose concentration in the range of 0-10 mM.