Monolithic Biosensor for Gene-Based Disease Detection

Abstract

In this paper, charge-modulated field effect transistor based detection circuit is presented for the purpose of electrical detection of DNA hybridization. The readout circuit consists of a drain follower and a compensated differential amplifier. It is able to achieve a voltage gain of 56.94 dB in the frequency range up to 6.79 kHz using 0.18μm Silterra CMOS process. The compensation technique is used in the detection circuit in order to improve the phase margin to 52.66o. The proposed potentiometric biosensor eliminates the need for a reference electrode which can offer great potential for miniaturized sensor array that would enable a massive parallel detection of DNA assay.