Challenges and Advances in the Surface Chemistry of Graphene Field-Effect Biosensors

Abstract

Graphene is particularly well-suited for the fabrication of field-effect biosensors (bioGFETs) [1], due to its chemical stability in aqueous media and its reduced dimensionality resulting in an electrical conductivity highly sensitive to biochemical processes occurring at its surface. The selectivity of GFETs for specific molecular targets, however, must be engineered with the addition of biorecognition elements such as antibodies or nucleic acids. Immobilizing such bioreceptors hinges on introducing chemically addressable moieties on the graphene, without impeding the electrical sensitivity. In this talk, I will first present our work on optimizing the chemical functionalization of graphene to combine bioconjugation and electrical signals. I will describe our findings on controlling various functionalization routes, both covalent and non-covalent, with a particular focus on our recent advances in gate-controlled surface chemistry on graphene [2]. I will also describe our current efforts to develop parallelized instrumentation for high-throughput fabrication and characterization of on-chip biosensors [3]. Finally, I will outline our translational perspectives aimed at adapting nanocarbon-based bioFETs into lab-on-a-chip platforms for diagnostic applications. [1] Béraud et al . Analyst, 146, 403 (2021) [2] Bazán et al . Nano Letters 22, 2635 (2022) [3] Bencherif et al . npj 2D materials and applications, 8, 53 (2024)