Interfacial Capacitance of Graphene Oxide Films Electrodes: Fundamental Studies on Electrolytes Interface Aiming (Bio)Sensing Applications

Autor(es)

Pessanha, Tatiana M. ^[1] ; Paschoalino, Waldemir J. ^[1] ; Deroco, Patricia B. ^[1] ; Kogikoski, Sergio ^{[1, 2]} ; De Moraes, Ana C. M. ^{[1, 3]} ; Castro Silva, Cecilia Carvalho ^[4] ; Kubota, Lauro T. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas, Inst Chem, Dept Analyt Chem, POB 6154, BR-13084971 Campinas, SP - Brazil

^[2] Univ Potsdam, Inst Chem, Phys Chem, Karl Liebknecht Str 24-25, D-14476 Potsdam - Germany

^[3] Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 - USA

^[4] Univ Prebiteriana Mackenzie, MackGraphe Graphene & Nanomat Res Ctr, BR-01302907 Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Electroanalysis; JUL 2021.
• Citações Web of Science: 0

Resumo

The understanding of bidimensional materials dynamics and its electrolyte interface equilibrium, such as graphene oxide (GO), is critical for the development of a capacitive biosensing platform. The interfacial capacitance (C-i) of graphene-based materials may be tuned by experimental conditions such as pH optimization and cation size playing key roles at the enhancement of their capacitive properties allowing their application as novel capacitive biosensors. Here we reported a systematic study of C-i of multilayer GO films in different aqueous electrolytes employing electrochemical impedance spectroscopy for the application in a capacitive detection system. We demonstrated that the presence of ionizable oxygen-containing functional groups within multilayer GO film favors the interactions and the accumulation of cations in the structure of the electrodes enhancing the GO C-i in aqueous solutions, where at pH 7.0 (the best condition) the C-i was 340 mu F mg(-1) at -0.01 V vs Ag/AgCl. We also established that the hydrated cation radius affects the mobility and interaction with GO functional groups and it plays a critical role in the Ci, as demonstrated in the presence of different cations Na+=640 mu F mg(-1), Li+=575 mu F mg(-1) and TMA(+)=477 mu F mg(-1). As a proof-of-concept, the capacitive behaviour of GO was explored as biosensing platform for standard streptavidin-biotin systems. For this system, the C-i varied linearly with the log of the concentration of the targeting analyte in the range from 10 pg mL(-1) to 100 ng mL(-1), showing the promising applicability of capacitive GO based sensors for label-free biosensing. (AU)

• Processo FAPESP: 17/05213-3 - Avaliação da atividade eletrocatalítica de sensores baseados em óxido de grafeno decorados com nanopartículas de Pt, Au e Ag por microscopia eletroquímica de varredura.
• Beneficiário: Waldemir José Paschoalino Junior
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 13/22127-2 - Desenvolvimento de novos materiais estratégicos para dispositivos analíticos integrados
• Beneficiário: Lauro Tatsuo Kubota
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 14/50867-3 - INCT 2014: Instituto Nacional de Ciência e Tecnologia de Bioanalítica
• Beneficiário: Marco Aurelio Zezzi Arruda
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 16/14507-8 - Estudos das Propriedades Estruturais e Eletroquímicas de Filmes Nanoestruturados baseados em DNA
• Beneficiário: Sergio Kogikoski Junior
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado