Electrooxidation and Determination of Dopamine Using a Nafion®-Cobalt Hexacyanoferrate Film Modified Electrode

Sensors

Suely S. L. Castro¹  Roger J. Mortimer³  Marcelo F. de Oliveira² 

[1]UERN - FANAT - Departmento de Química, 59600-010 – Mossoró, RN, Brazil

[2]USP – Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto- Departamento de Química, 14040-901 – Ribeirão Preto, SP, Brazil

[3]Loughborough University - Department of Chemistry, Loughborough, LE11 3TU, UK

关键词: Cobalt hexacyanoferrate;    chemically modified electrode;    dopamine;    voltammetry;    rotating disk electrode;   

DOI  :  10.3390/s8031950

来源: mdpi

【 摘 要 】

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^-1 s^-1 at a concentration of 5.0 × 10^-5 mol 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^-5 to 5.0 × 10^-4 mol L^-1 with a slope of 23.5 mA mol^-1 L and a linear correlation coefficient of 0.999. The detection limit of this method was 8.9 × 10^-6 mol L^-1 and the relative standard deviation for five measurements of 2.5 × 10^-4 mol L^-1 dopamine was 0.58%.

【 授权许可】

Unknown   
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