1Pace University, Department of Chemistry, Pleasantvile, NY 10570-2799, U.S.A.
2Inorganic Chemistry Laboratory, Molecular Sensor Unit, University of Oxford, South Parks Road, Oxford, OX1 3QR, U.K.
Even though the use of enzymes as useful analytical reagents when immobilized onto a transducer such as an electrochemical device has been reported in the literature for nearly two decades, the direct, i.e. unmediated electrochemistry of enzymes is, nevertheless, a rather recent development. Efforts will be made to introduce the fundamental basis for protein-surface interactions with emphasis on the powerful technique of cyclic voltammetry. The experimental schemes and ample examples as performed in our laboratory will also be presented to illustrate the kinetic and thermodynamic information acquired based on such enzymatic systems. It is believed that forther acquisition of knowledge in the field combined with findings from other complementary disciplines such as modeling and simulation, instrumental computerization and miniaturization, and on-line adaptability will ultimately pave the way toward the universal acceptance of biosensor and actuators for chemical analysis.