ABSTRACT
For over 20 years, our group has been developing voltammetric detection methods for immunoassays. These assays have come to be generally referred to as electrochemical immunoassay (ECIA). The main impetus for this work has been the exciting possibility of developing very sensitive assays by combining the excellent sensitivity of voltammetry with the exceptional selectivity of antibody-antigen binding. We have also been encouraged by the promise of ECIA for overcoming problems associated with other major types of immunoassays. Radioimmunoassays, which use radioactive labels, pose health hazards and disposal problems; and immunoassays with optical detection are often unsuitable for the analysis of colored or turbid samples. Electrochemical immunoassay is free of these problems; and, moreover, has the advantage of being able to handle extremely small samples because electrochemistry is an interfacial process in which the important reactions occur at the electrode-sample interface, not in bulk solution.
