Elucidation of the Electrochemical Oxidation Mechanism of the Antioxidant Sesamol on a Glassy Carbon Electrode

The dissociation constant of Sesamol (5-hydroxy-1,3-benzodioxol) was determined from the dependence of the UV-visible spectra with the medium acidity. A pK value of 10.1 ± 0.1, corresponding to the hydroxyl group, was obtained. The oxidation of sesamol was investigated on carbon electrodes using con...

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Detalhes bibliográficos
Autores: Estévez Brito, Rafael, Rodríguez Mellado, José Miguel, Maldonado, Pilar, Ruiz Montoya, Mercedes, Palma López, Alberto, Morales Carrillo de Albornoz, Emilio
Formato: artículo
Fecha de publicación:2014
País:España
Recursos:Universidad de Huelva (UHU)
Repositorio:Arias Montano. Repositorio Institucional de la Universidad de Huelva
Idioma:inglés
OAI Identifier:oai:ariasmontano.uhu.es:10272/23349
Acesso em linha:https://hdl.handle.net/10272/23349
Access Level:acceso abierto
Palavra-chave:Sesamol
1,4-benzoquinone
Electrode kinetics
Antioxidants
Glassy carbon electrode
3303 Ingeniería y Tecnología Químicas
Descrição
Resumo:The dissociation constant of Sesamol (5-hydroxy-1,3-benzodioxol) was determined from the dependence of the UV-visible spectra with the medium acidity. A pK value of 10.1 ± 0.1, corresponding to the hydroxyl group, was obtained. The oxidation of sesamol was investigated on carbon electrodes using controlled-potential electrolysis, linear-sweep cyclic voltammetry and measurements at the foot of the first oxidation peak. Up to three oxidation peaks and one reduction peak were found. The dioxol ring of the dissociated sesamol undergoes a cleavage to give 3-substituted 1,4-benzoquinone, being the rate-determining step the second electron transfer. The formation of radicals in the ring cleavage explains in part the ability of sesamol to interact with reactive oxygen species (ROS).