Electrochemical Property of Myoglobin-chitosan-colloid Gold Film Modified Glass Carbon Electrode

Myoglobin(Mb)-chitosan-colloidal gold films were made by casting a solution of Mb,chitosan and colloidal gold on glass carbon electrodes.Mb incorporated in chitosan-colloidal gold films gave a pair of(stable,) well-defined,and quasi-reversible cyclic voltammetric peaks at about-0.20 V(vs.Ag/AgCl) in(0.1 mol/L) NaAc-HAc buffer(pH=5.4),being the characteristic peaks of the Mb heme Fe(Ⅱ)/Fe(Ⅲ) redox couple.The effects of scan rate,pH and concentration of buffer solutions on the electrochemical(behavior) of Mb were studied in detail.Position of the Soret absorbance band suggests that Mb in chitosan-(colloidal) gold kept its secondary structure similar to the native states.Oxygen was catalytically reduced by Mb in(chitosan-)colloidal gold films.