Electrochemically Active L-Cysteine Gold Modified Electrodes

Autor(es)

de Oliveira, Fernando C. M. ^[1] ; Serrano, Silvia H. P. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo. Inst Chem

^[2] Univ Sao Paulo. Inst Chem

• Tipo de documento: Artigo Científico
• Fonte: Electrochimica Acta; v. 125, p. 566-572, APR 10 2014.
• Citações Web of Science: 1

Resumo

Gold electrodes were easily modified using MPA (3- mercaptopropionic acid) to produce a self assemble monolayer, SAM, in which electrochemically active cysteine molecules were anchored to produce Au/MPA and Au/MPA/CSH electrodes. The functional groups, present on the modified electrode surfaces, were identified using cyclic voltammetry and ferricyanide ions, an electrochemical probe, at variable pH values. The steps which describe the global electrode process were identified and characterized using cyclic voltammetry. It involves the deprotonation of the R-SH superficial groups; production of R-S free radicals from R-S- electrochemical oxidation and attack and of R-S free radicals to the ASH adjacent molecules on the electrode surface, followed by the second electrochemical oxidation step to produce RSSR. The Au/MPA/CSH electrode showed electrocatalytic activity toward oxidation of quercetin in the range of 0.50 to 12.2 mu molL(-1) with a detection limit of 0.15 mu molL(-1). (C) 2014 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 09/18223-0 - Potencialidades analíticas de derivados de ligninas provenientes do processo Kraft (licor negro): extração de metais pesados e desenvolvimento de sensores voltamétricos
• Beneficiário: Silvia Helena Pires Serrano
• Modalidade de apoio: Auxílio à Pesquisa - Regular