Determination of dopamine in synthetic cerebrospinal fluid by SWV with a graphite-polyurethane composite electrode

Autor(es)

Toledo, R. A. de ; Santos, Mauro Coelho dos ^[2] ; Cavalheiro, E. T. G. ; Mazo, L. H.

• Tipo de documento: Artigo Científico
• Fonte: ANALYTICAL AND BIOANALYTICAL CHEMISTRY; v. 381, n. 6, p. 1161-1166, Mar. 2005.
• Área do conhecimento: Ciências Exatas e da Terra - Química
• Assunto(s): Eletroquímica Dopamina Oxidação

Resumo

This work describes an electroanalytical investigation of dopamine using cyclic voltammetry ( CV) and the graphite-polyurethane composite electrode (GPU). In CV studies, well-defined redox peaks characterize the oxidation process at the GPU electrode, which is indicative of electrocatalytic effects associated with active sites on the GPU electrode surface. A new analytical methodology was developed using the GPU electrode and square wave voltammetry (SWV) in BR buffer solution (0.1 mol L-1; pH 7.4). Analytical curves were constructed under optimized conditions ( f= 60s(-1), Delta E-a= 50 mV, Delta E-I= 2 mV) and detection and quantification limits of 6.4x10(-8) mol L-1 (12.1 mu g L-1) and 5.2x10(-6) mol L-1 (0.9 mg L-1), respectively, were achieved. The precision of the method was checked by performing ten successive measurements for a 9.9x10(-6) mol L-1 dopamine solution. For intra-assay and interassay precisions, the relative standard deviations were 1.9 and 2.3%, respectively. In order to evaluate the developed methodology, the determination of dopamine was performed with good sensitivity and selectivity, without the interference of ascorbic acid in synthetic cerebrospinal. fluid, which indicates that the new methodology enables reliable analysis of dopamine. (AU)

• Processo FAPESP: 01/06029-3 - Eletrocatalise da oxidacao de pequenas moleculas organicas com eletrodos modificados.
• Beneficiário: Mauro Coelho dos Santos
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 01/14629-0 - Estudo eletroquímico e desenvolvimento de novas metodologias eletroanalíticas para a determinação de antidepressivos tricíclicos e neurotransmissores
• Beneficiário: Renata Alves de Toledo
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 03/02630-0 - Desenvolvimento e aplicação de eletrodos compósitos à base de poliuretana/grafite e borracha de silicone/grafite
• Beneficiário: Éder Tadeu Gomes Cavalheiro
• Modalidade de apoio: Auxílio à Pesquisa - Regular