Integrated nanostructures for direct detection of DNA at attomolar concentrations

We report an integrated chip that senses nucleic acid biomarkers at exceptionally low concentrations. To achieve such sensitivities we exploit four concepts. (1) Nanostructured electrodes allow efficient display of probe sequences. (2) The use of uncharged probe sequences lowers the background signal in our read-out system. (3) Electrocatalysis provides built-in amplification of the electrical signal that reports hybridization events. (4) An …