Graphene Biosensors Operated in DC Transistor and AC Electrochemical Modes for DNA Sensing

• Main Author: Pinzon, Edgar [UNESP]
• Publication Date: 2023
• Other Authors: Domingues, Telma, Wrege, Rodrigo, Lopes, Lais C. [UNESP], Borme, Jerome, Daros, Thiago, Piteira, Joao, Costa, Bruno M., Bueno, Paulo R. [UNESP], Alpuim, Pedro
• Format: Conference object
• Language: eng
• Source: Repositório Institucional da UNESP
• Download full: http://dx.doi.org/10.1109/SENSORS56945.2023.10324951; https://hdl.handle.net/11449/297681
• topic: biosensor; CMOS; Graphene; quantum capacitance

Graphene is considered for different technological applications, particularly biosensing, due to its unique electrical and electronic properties, such as its ambipolar transport and ballistic electron dynamics. Thus, graphene-based setups that allow fast and simple access to its quantum properties are required to advance in the design of high-performance devices. Non-destructive methodologies based on small electrical perturbations offer the possibility of accessing graphene's electronic structure (V-shaped DOS) in mild experimental conditions. Here, we present a device comprising 20 graphene functionalized channels per chip operated in two modes: a 3-terminal DC transistor and a 2-terminal AC electrochemical setup. Both setups resolved the graphene electronic structure, used as a transduction signal to detect four brain tumor single-stranded DNA biomarkers with a single genetic mutation. The device detected the four cancer biomarkers in the attomolar range (∼ 10 aM) in DC transistor mode. A detection limit of 1 aM was achieved in the AC electrochemical mode for the DNA mutation studied. We present a CMOS integrated circuit for fast readout of the multiplexed graphene sensor arrays.