The rapid and sensitive detection of pathogens is critical for disease intervention strategies, as well as the control and prevention of pandemics and acts of bioterrorism. There is a need to be able to perform pathogen detection, both in laboratory facilities, and under field conditions. Consequently, biosensing platform technologies are under development to allow for both applications. Current methods of virus and bacteria detection generally employ antibody-based assays such as enzyme-linked immunosorbant assays (ELISA), fluorescent antibody assays, or serologic evaluation for exposure. Many of these assay methods provide only a limited level of sensitivity, thus low level pathogen detection generally requires nucleic acid amplification coupled with polymerase chain reaction (PCR) assays.

More recently, other diagnostic methods such as microcantilevers, evanescent wave biosensors, immunosorbant electron microscopy, and atomic force microscopy have been investigated to overcome some of the limitations of sensitivity, but these new techniques are unable to effectively discriminate between types and/or species of pathogen with reasonable sample throughput. The research directions for improvement of biosensing methods require reduction or elimination of sample preparation or amplification procedures. Detection and discrimination of specimens in complex biological media are also a necessity, together with reproducible results, cost and time effectiveness, and ease of use under most conditions.