Cutting out the middleman: DNA biosensors based on electrochemical oxidation

There is considerable enthusiasm over electrochemical techniques in biotechnology, including the development of electrochemical biosensors for DNA hybridisation. The development of assay techniques that have the convenience of solid-phase hybridisation and are rapid, sensitive and readily multiplexed will have a significant impact on diagnostics and genomics. Because electrochemistry requires a solid electrode, there is a natural marriage between electrode detection and surface hybridisation. Modern electrochemical approaches include the detection of hybridisation at electrode surfaces using duplex-specific indicators and the shuttling of electrons from surface-bound nucleic acids to solid electrodes using soluble mediators with potentials matched to that of guanine.