title: Electrooxidation and Determination of Dopamine Using a Nafion®-Cobalt Hexacyanoferrate Film Modified Electrode.
abstract: The electrocatalysis of dopamine has been studied using a cobalt hexacyanoferrate film (CoHCFe)-modified glassy carbon electrode. Using a rotating disk CoHCFe-modified electrode, the reaction rate constant for dopamine was found to be 3.5 × 105 cm³ mol-1s-1at a concentration of 5.0 × 10-5mol L-1. When a Nafion®film is applied to the CoHCFe-modified electrode surface a high selectivity for the determination of dopamine over ascorbic acid was obtained. The analytical curve for dopamine presented linear dependence over the concentration range from 1.2 × 10-5to 5.0 × 10-4mol L-1with a slope of 23.5 mA mol-1L and a linear correlation coefficient of 0.999. The detection limit of this method was 8.9 × 10-6 mol L-1and the relative standard deviation for five measurements of 2.5 × 10-4 mol L-1dopamine was 0.58%.
authors.affiliation: UERN - FANAT - Departmento de Química, 59600-010 - Mossoró, RN, Brazil.
authors.forename: Suely S L
authors.initials: SS
authors.lastname: Castro
authors.affiliation: Loughborough University - Department of Chemistry, Loughborough, LE11 3TU, UK.
authors.forename: Roger J
authors.initials: RJ
authors.lastname: Mortimer
authors.affiliation: USP - Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto- Departamento de Química, 14040-901 - Ribeirão Preto, SP, Brazil.
authors.forename: Marcelo F
authors.initials: MF
authors.lastname: De Oliveira
authors.affiliation: UNESP - Instituto de Química- Departamento de Química Analítica, 14800-900 - Araraquara, SP, Brazil. nrstradi@iq.unesp.br.
authors.forename: Nelson R
authors.initials: NR
authors.lastname: Stradiotto
keywords: Cobalt hexacyanoferrate; chemically modified electrode; dopamine; rotating disk electrode.; voltammetry