Amperometric detection of DNA hybridization using a multi-point, addressable electrochemical device

A novel device was designed for the multipoint addressable detection of DNA hybridization. Row and column electrodes array were orthogonally arranged, and the microwells were assembled on the crossing points of the row/column electrodes to form a 4 × 4 microwell array. Amperometric signals at the individual microwells could be detected separately on the basis of redox cycling of localized electroactive species occurring between the electrodes. Immobilization and hybridization of DNA could block the redox cycling of Fe(CN)64−/Fe(CN)63− at the designated microwells, resulting in the reduction of current response. This device had been used to detect DNA hybridization with excellent sensitivity (0.03 μM) and selectivity. The device can be applied to comprehensive and high-throughput detection and imaging of biochemical species.