Advances in electrochemical immunosensors

The developments in the field of electrochemical immunosensors and immunoassays are reviewed. The enzyme labels suitable for amperometric, potentiometric and conductimetric detection are mentioned. Indirect immunosensors (i.e., that involving enzymatic or electroactive labels) use either heterogeneous or homogeneous formats. Immunoelectrodes are based on conventional electrodes, semiconductor devices are represented by ISFETs and light addressable potentiometric sensors (LAPS). Direct label-free monitoring of immunoreactions is demonstrated on capacitance systems and pulsed detection using polypyrrole-modified electrodes. The approaches to regeneration of sensing surfaces are discussed. Examples are given on applications of electrochemical immunodevices in clinical medicine and in environmental monitoring.