Electrochemical Chiral Sensors and Biosensors

Abstract

AbstractChiral molecular recognition depends on difference in stability constants of diastereomeric complexes with applied selectors, different migration of enantiomers based on the formation and dissociation of diastereomeric complexes, and on a different interaction rate of enantiomers with selector. Selected examples of electrochemical enantioselective sensors and biosensors based on different mechanisms of molecular recognition are reviewed. Chemical chiral sensors can be based on plasticized membranes incorporating a chiral ionophore, on differences of Gibbs free energy for interphase electron transfer, or on the use of molecularly imprinted polymers and electrodeposited conducting polymers doped with chiral ions. Reported chiral biosensors include enzymatic devices and immunosensors. Especially pronounced enantioselectivity of enzymatic biosensors can be employed practically, e.g., in food control, showing chiral discrimination better that two orders of magnitude. Developed, so far, chemical sensors show enantioselectivity usually not exceeding two orders magnitude and require further investigation for any practical analytical applications.