Label-free detection of DNA hybridization with Au/SiO/sub 2//Si diodes and poly-Si TFTs

Label-free electrical detection of DNA hybridization has been achieved by employing Au/SiO/sub 2//Si MOS diodes and poly-Si TFTs. The detection is based on the modulation of the gate voltage associated with the increased negative charge on the gate upon hybridization. The method can be applied to other bio-reactions that result in a modification of surface dipoles.