Affinity electrochemical biosensors for pollution control

Disposable, electrochemical DNA-based biosensors have been exploited for th e determination of low-molecular-weight compounds with affinity for nucleic acids. The application is related to the molecular interaction between the surface-linked DNA obtained from calf thymus and the target pollutants or drugs, in order to develop a simple device for rapid screening of genotoxic or similar compounds. The determination of such compounds was measured by their effect on the oxidation signal of the guanine peak of the DNA immobil ized on the electrode surface and investigated by chronopotentiometric or s quare-wave voltammetric analysis. The DNA biosensor is able to detect known intercalating and groove-binding compounds such as daunomycin, polychlorin ated biphenyls (PCBs): aflatoxin B1, and aromatic amines. Applicability to river and waste water samples is discussed and reported.