Electrochemical Analysis of Metabolites as a Method for Cytochromes P450 Activity Determination

The review deals with the electrochemical methods for determination of metabolites of cytochromes P450 catalyzed reactions. We have focused on the electrochemical determination of metabolites of drugs and some endogenous compounds. We have reviewed bielectrode systems for determination of cytochrome P450 activity, where one electrode serves as a matrix for enzyme immobilization and a source of electrons for heme iron ion reduction and initialization of the catalytic reaction towards a substrate and the second one is being used for quantification of the products formed by their electrochemical oxidation. Such systems allow one to elude additional steps of separation of reaction substrates and products. The review also includes discussion of the ways to increase the analytical sensitivity and decrease the limit of detection of the investigated metabolites by chemical modification of electrodes. We demonstrate the possibilities of these systems for cytochrome P450 kinetics analysis and the perspectives of their further improvement, such as increasing the sensitivity of metabolite electrochemical determination by modern electrode modificators, including carbon-based, and construction of devices for automatic monitoring of the products.