The Impact of Pesticides - Academy Publish

ELECTROCHEMICAL BIOSENSORBiosensors have recently been defined as analytical devices incorporating abiological material (e.g. enzymes, antibodies, nucleic acids, cell receptors, tissue,etc.), a biologically derived material (e.g. recombinant antibodies, engineeredproteins, Aptamers, etc.) or a biomimic (e.g., synthetic catalysts, combinatorialligands and imprinted polymers) intimately associated with or integrated within aphysicochemical transducers which may be optical, electrochemical, thermometric,piezoelectric, magnetic etc. The biosensors can be classified according to theirtransduction methods and biological materials. There are three main classes ofbiological recognition materials which are used in biosensors applications. These are(i) enzymes, (enzyme based biosensors) (ii) antigen-antibodies (immunosensors)and (iii) nucleic acids (DNA based biosensors) (Sassolas et al., 2008). When thetransducer used is based on electrochemical principle then it is called aselectrochemical biosensor. These biosensors are mainly based on the observation ofcurrent, potential, impedance, conductance changes due to interactions occurring atthe sensor (electrode) sample matrix interface. They are generally classifiedaccording to the observed parameter such as current (amperometric), potential(potentiometric), impedance (impedimetric) and conductance (conductometric).Fig. 2. Pictorial presentation of the action of organophosphorous compounds onacetylcholiesterase enzymeAcademyPublish.org - The Impact of Pesticides394