Electrochemical response of hemoglobin

Abstract

Electron transfer between heme protein and electrode surface can be enhanced by electrode modifiers such as clays. Using hemoglobin as sensor relays on its possibility to retain native structure that enables hemoglobin to shift conformation. Therefore, electrochemical investigation of hemoglobin response at extreme pH did not take attention. At extreme pH values protein denaturation occurs resulting in conformation loss. The aim of this paper was to investigate electrochemical behavior of hemoglobin supported on smectite in alkaline media. Hemoglobin was immobilized on acid activated clay, bare and modified by SDS. The adsorption of hemoglobin was slightly increased by the presence of SDS on the electrode surface. All samples showed peak at -0.45 V ascribed to reduction pair of heme Fe(III)/Fe(II). Denaturation of hemoglobin imparted chemically by SDS or electrochemically by cycling in cathodic potential range, led to development of new peak at potential around -0.7 V in alkaline media. This feature might be useful for studying and determination of different hemoglobin types.