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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Evaluation of a Graphite-Polyurethane Composite Electrode Modified with Copper Nanoparticles as an Amperometric Flow Detector in a Wall-Jet System for the Determination of Cysteine

Texto completo
Autor(es):
Mattioli, Isabela A. [1] ; Schildt, Leticia F. L. [1] ; Cervini, Priscila [1] ; Saciloto, Thalita R. [1] ; Cavalheiro, Eder T. G. [1]
Número total de Autores: 5
Afiliação do(s) autor(es):
[1] Univ Sao Paulo, Inst Quim Sao Carlos, Av Trabalhador Sao Carlene 400, BR-13566590 Sao Carlos, SP - Brazil
Número total de Afiliações: 1
Tipo de documento: Artigo Científico
Fonte: Journal of the Brazilian Chemical Society; v. 31, n. 2, p. 370-380, FEB 2020.
Citações Web of Science: 0
Resumo

A graphite-polyurethane composite electrode (GPUE) was modified by electrodeposition of copper nanoparticles (CuNP) followed by electrochemical treatment in NaOH (GPUE-CuNP), in order to prepare an amperometric sensor for the determination of cysteine (Cys). Cyclic votammograms of Cys solutions at GPUE-CuNP allowed the description of a sequence of electrochemical reactions involving Cys oxidation and Cu-0/Cu+ equilibrium, generating a stable Cys-Cu+ complex. The presence of these nanoparticles was confirmed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) data. Hence, the developed device was then used as a Cys amperometric flow detector in a wall-jet system, after evaluation of flow injection parameters in an undescribed approach. In this system, a limit of detection (LOD) of 4.24 mu mol L-1 was obtained with an analytical frequency of 36 determinations h(-1). Intra-day and inter-day reproducibility and repeatability of the modified surface was evaluated. Then the GPUE-CuNP performance was investigated in the determination of Cys content in food supplements. Interference tests were carried out with pyridoxine, ascorbic acid, tryptophan and SO42- ions. The main interference was attributed to the interaction of some of these substances with copper oxides. (AU)

Processo FAPESP: 18/11071-0 - Desenvolvimento e aplicação de eletrodos compósitos impressos descartáveis à base de nanopartículas metálicas e grafite-poliuretana
Beneficiário:Isabela Alteia Mattioli
Linha de fomento: Bolsas no Brasil - Doutorado Direto
Processo FAPESP: 17/04211-7 - Desenvolvimento de tintas à base de nanopartículas metálicas e polímeros para construção de eletrodos compósitos convencional e impresso e suas aplicações
Beneficiário:Éder Tadeu Gomes Cavalheiro
Linha de fomento: Auxílio à Pesquisa - Regular