Fully electronic DNA hybridization detection by a standard CMOS biochip

A novel solid-state biosensor for label-free detection of DNA hybridization is presented. The new device is realized in a standard CMOS process, thus allowing the realization of low-cost, portable, fully integrated devices. The detection mechanism is based on the field-effect of the intrinsic negative electric charge of DNA molecules which modulates the threshold voltage of a floating-gate MOS transistor. A fluid cell was developed for delivering DNA samples on the active surface of the chip. The device has an integrated, individual counter-electrode, so dry measurements are possible increasing lifetime of the chip and speeding up the experiment. Successful measurements on a first prototype of the chip, hosting 16 sensors individually addressable, are provided as proof of concept.