Functionalized graphene oxide (GO) and reduced graphene oxide (rGO): Effect on the AC and DC electrical transduction of bio-interactions

• Grant number: 24/01961-9
• Support Opportunities: Scholarships in Brazil - Master
• Start date: March 01, 2024
• End date: February 28, 2026
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Rafael Furlan de Oliveira
• Grantee: Ana Vitória Ferreira Deleigo
• Host Institution: Centro Nacional de Pesquisa em Energia e Materiais (CNPEM). Ministério da Ciência, Tecnologia e Inovação (Brasil). Campinas , SP, Brazil
• Associated research grant: 21/06238-5 - Functionalized solution-processed 2D materials: development of prototyping electric sensors and biosensors, AP.JP

Abstract

Graphene oxide (GO) and its reduced form (rGO) are remarkable 2D materials (2DMs), characterized by their unique properties and various functional oxygenated groups. The functionalization of GO and rGO enables the introduction of new functionalities to these materials, for example, via the immobilization of chemical or biological receptors for applications in sensors and biosensors, providing selectivity to a specific analyte. This functionalization can be achieved through covalent or non-covalent bonding directly on the basal plane or at the periphery of the material's sheet. In this context, sensors and biosensors based on GO and rGO can be developed using electrolyte-gated transistors (EGTs), where the common gate dielectric of transistors is replaced by an electrolytic solution. The use of aqueous electrolytes provides a favorable environment for molecules and biomolecules, making EGTs very appealing for sensing and biosensing. This project aims to understand how the functionalization of GO and rGO films through both covalent and non-covalent methods employing the same biomolecule distinctly affects the AC and DC electrical transduction of the bioreceptor-analyte interaction. To achieve this, EGT devices based on rGO will be functionalized with specific bioreceptors through different modification routes such as epoxide ring opening reaction or À-À stacking with an appropriate molecular linker. The biospecific interaction between receptor and analyte will be assessed via DC methods such as current-voltage measurements, and AC methods such as electrical impedance spectroscopy, as well as a combination of AC/DC methods.