Gold nanoparticle-mediated electron transfer of cytochrome c on a self-assembled surface

Autor(es)

Luz, Roberto A. S. ^[1] ; Crespilho, Frank N. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Quim Sao Carlos, BR-13560970 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: RSC ADVANCES; v. 6, n. 67, p. 62585-62593, 2016.
• Citações Web of Science: 6

Resumo

The presence of gold nanoparticles (AuNPs) at the protein/electrode interface has a significant impact on the electrodic microenvironment, and allows the optimization of the activity catalysis as well as electrochemical properties. Here, we report a novel and accurate methodology to observe AuNP mediated electron transfer mechanism from Cytochrome c (Cyt c) to a polycrystalline gold surface. Poly(allylamine hydrochloride) molecules (PAH) were used as spacers between Cyt c and the electrode surface, and the electron rate constant within the PAH layer was measured in the presence and absence of AuNPs. Based on cyclic voltammetric experiments and Marcus theory, a four-fold increase in the electron rate constant was observed in the presence of AuNPs, and the reorganization energy was estimated to be 0.49 eV. Furthermore, AuNPs decreased the effective distance between the redox center of Cyt c and the electrode surface by 20%. These results suggest that the electron transfer properties of Cyt c based protein electrodes are significantly enhanced in the presence of the AuNPs. (AU)

• Processo FAPESP: 13/04663-4 - Bioeletrodos enzimáticos aplicados em biocélulas a combustível: simulação e experimental
• Beneficiário: Frank Nelson Crespilho
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 13/14262-7 - Filmes nanoestruturados de materiais de interesse biológico
• Beneficiário: Osvaldo Novais de Oliveira Junior
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 15/16672-3 - Desenvolvimento de Bioeletrodos de Alto Desempenho para Miniaturização de Biocélulas a Combustível
• Beneficiário: Frank Nelson Crespilho
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 09/17898-4 - Estudo Eletroquímico da Interação entre Enzimas e Nanoparticulas para Aplicação em Biodispositivos
• Beneficiário: Roberto Alves de Sousa Luz
• Modalidade de apoio: Bolsas no Brasil - Doutorado