An electrochemical DNA biosensor is proposed to simultaneously detect and identify multiple nucleic acid determinants of a variety of pathogens using a combination of electronic hybridization, fluidics, and electrochemical detection. The biosensor would consist of a sample lysis and electronic hybridization/release chamber fluidically connected to an electrochemical flow cell for detection, and would incorporate Xanthon's patented platform technology of electrochemical detection of nucleic acids. With this method, specific target nucleic acid species captured by oligo capture probes are directly detected by the electrochemical oxidation of guanine, an endogenous component of the nucleic acid targets. This provides a method of rapid, highly sensitive, and specific DNA detection without the need for complicated sample purification procedures, exogenous labels, labile reagents, or expensive, heavy, power-hungry instrumentation. Upon successful demonstration of the feasibility of the basic components, plans for further miniaturization and integration of the components will proceed toward development of a rugged, easy-to-use handheld unit that will take further advantage of the power and simplicity of direct electrochemical detection, in addition to the economy of time, space, and reagents made possible by microfluidics and electronic hybridization. In addition to military applications, development of such devices would provide prompt detection of potential bio-terrorist attacks, and find wide application for the detection of pathogens in medical diagnostics, point-of-care clinical settings, food production, environmental monitoring, agriculture, and various industrial settings.
