Direct Electrochemistry of Hemoglobin on Electrodeposited Three-Dimensional Interconnected Graphene-Silver Nanocomposite Modified Electrode

A three-dimensional electroreduced graphene oxide (3DGR) and silver (Ag) nanocomposite was fabricated by electrodeposition directly on the electrode surface for modification. N-butylpyridinium hexafluorophosphate (BPPF6) was used to prepare a carbon ionic liquid electrode (CILE) and acted as the basic working electrode. Hemoglobin (Hb) was further casted on the surface of Ag/3DGR/CILE to result a bioelectrode. Direct electrochemistry of Hb on the modified electrode was accelerated with a pair of well shape redox waves on cyclic voltammogram, showing the realization of direct electron transfer. The presence of high conductive Ag/3DGR composite on the electrode facilitated the electron transfer rate from the electroactive center of Hb to the electrode. Electrochemical behaviors of Hb on the modified electrode were checked and the electrochemical parameters were calculated.