The preparation of hemoglobin based electrode on the basis of MOF-graphene oxide nano-complex and the investigation on its electro-catalytic effect on the reduction of H2O2

Abstract

The co-mixture of graphene oxide and metal-organic framework material is proposed to act as a bio-macromolecule supporter. Hemoglobin based-electrode is prepared via the conventional drip-casting method, and heme protein molecules are incorporated into the nano-complex. The role of oxygen-containing groups on graphene oxide in the mutual interactions between elements within nano-composite, as well as the integrated hemoglobin and its impact on enzyme-involved electro-catalysis, are the primary objectives of the current manuscript. The analysis in the experimental results manifests that the existence of oxygen-containing groups onto GO would contribute to the improvement in the orderliness of nano-complex with hemoglobin molecule and the formation of an amphiphilic micelle-like structure with a hydrophobic outer surface and hydrophilic core. The mutual interaction between graphene oxide and a metal-organic framework would alleviate the binding strength of hemoglobin with metal-organic framework to distort the aboriginal configuration of the heme site within the protein molecule. The synergistic effect of multiple interactions between metal-organic framework and graphene oxide with oxygen-containing groups leads to the disappearance of the electrochemical signal for the electro-active sites in graphene oxide. The interaction between elements of nano-complex would depress the electro-activity of redox sites in nano-composite, and the integrated heme protein could play the role of the primary electro-active species in nano-complex with protein accommodation. The existence of oxygen-containing groups on graphene oxide could slow down the charge transportation process via the mutual interaction between heme protein and graphene oxide to restrain the electro-catalytic efficiency.