Abstract
A variety of spectroelectrochemical methods for characterization of redox property of proteins are reviewed. Thermodynamic parameters such as the formal potential of protein can be obtained with these methods. Special attention is paid to the conditions to establish the Nernst equilibrium for the spectroelectrochemical techniques. Recent development of these techniques and its applications are reviewed in view of direct and indirect electrochemistry. Some kinetic approaches for the determination of thermodynamic parameter of redox proteins are also briefly sited.