Protein film electrochemistry

Protein film electrochemistry (PFE) is a powerful suite of electroanalytical techniques used to investigate the properties of redox proteins. The proteins under investigation are adsorbed as a (sub-)monolayer film on an electrode surface. Direct electron transfer between the immobilized protein and working electrode gives rise to an electrical current that visualizes and quantifies redox processes occurring within the protein. Advantages of PFE include low sample requirements — typically less than a nanomole protein — high sensitivity and the ability to resolve redox chemistry in the electrochemical potential and time domains. This Primer provides a guide to using PFE for quantitative thermodynamic and kinetic descriptions of half-reactions (redox reactions) and coupled chemical processes, including ligand binding, ligand unbinding and redox catalysis. Applications of PFE in developing biosensors, facilitating energy conversion and resolving enzyme mechanisms are highlighted. Finally, the state of the art and prospects for novel experimental and theoretical approaches are discussed.