Amplifying sensing performance through gold micropatterns-induced modulation of graphene's vertical electron transfer

Autor(es)

Hassan, Ayaz ; Colombo, Rafael N. P. ; Iost, Rodrigo M. ; Crespilho, Frank N.

• Tipo de documento: Artigo Científico
• Fonte: Electrochimica Acta; v. 466, p. 9-pg., 2023-08-25.

Resumo

High-quality graphene monolayers exhibit limited vertical electron transfer properties due to their inert basal plan structure, hampering their use in electrochemical sensing devices. Overcoming this limitation while maintaining the graphene's basal plane electrical conductivity is crucial for developing sensitive and efficient electrochemical sensors. In this study, we demonstrate that incorporating a gold support beneath graphene enhances its electrochemical activity by facilitating effective hybridizations between carbon atoms in graphene and gold atoms. To achieve this, micrometer-sized gold micropatterns were fabricated on Si/SiO2 substrates to support the graphene monolayer. The presence of gold significantly improved the electrochemical activity of graphene towards redox probes in solution (ferri-/ferrocyanide) as well as for adsorbed ferrocene, indicating a synergistic effect between graphene and gold. We further investigated the adsorption effects of double-stranded DNA on pristine graphene, bare gold, and graphene with a gold underlayer, revealing that the graphene-gold combination achieved a significantly lower limit of detection for DNA hybridization events, surpassing the other configurations. These findings highlight the importance of appropriate substrate selection in the design of graphene-based electrochemical sensors, particularly in the context of DNA recognition events. The proposed approach of incorporating a gold support beneath graphene holds promise for enhancing the performance of electrochemical sensing devices without compromising the intrinsic properties of graphene. (AU)

• Processo FAPESP: 19/12053-8 - Eletrodos de alto desempenho aplicados em baterias orgânicas e em biocélulas a combustível
• Beneficiário: Frank Nelson Crespilho
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 19/15333-1 - Células híbridas bio-foto-eletroquímicas para conversão de energia solar
• Beneficiário: Frank Nelson Crespilho
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 18/22214-6 - Rumo à convergência de tecnologias: de sensores e biossensores à visualização de informação e aprendizado de máquina para análise de dados em diagnóstico clínico
• Beneficiário: Osvaldo Novais de Oliveira Junior
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 21/05665-7 - Desenvolvimento de superfícies de Van der Waals para aplicação em biodispositivos
• Beneficiário: Rafael Neri Prystaj Colombo
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado