Poly(methylene blue)-modified electrode for indirect electrochemical sensing of OH radicals and radical scavengers

AUTOR(ES)

BRAUN, WALTER A., HORN, BRUNA C., HOEHNE, LUCÉLIA, STÜLP, SIMONE, ROSA, MARCELO B. DA, HILGEMANN, MAURÍCIO

FONTE

An. Acad. Bras. Ciênc.

DATA DE PUBLICAÇÃO

14/08/2017

RESUMO

ABSTRACT A new modified electrode for indirect sensing of OH· and radical scavengers was described. The electrochemical polymerization of methylene blue in aqueous solutions and the properties of the resulting films on a glassy carbon electrode were carried out using cyclic voltammetry. A surface coverage of 1.11 × 109mol cm2 was obtained, revealing a complete surface coverage of the polymeric film on the electrode surface. OH· was able to destroy the poly(methylene blue) film by exposure to a Fenton solution. The loss of the electrochemical signal of the residual polymeric film attached to the electrode surface was related to the extent of its dissolution. The applicability of the sensor was demonstrated by evaluating the OH radical scavenging effect on different concentrations of ascorbic acid. The obtained radical scavenging capacity were 31.4%, 55.7%, 98.9% and 65.7% for the ascorbic acid concentrations of 5, 10, 30 and 50 mM, respectively.

Documentos Relacionados

• Evaluation of chemical and mechanical resistance of virgin and recycled poly (ethylene terephthalate) and poly(methylene oxide) when applied as gravel pack in petroleum wells
• Development of poly (methylene blue) modified electrode for the determination eletroanalítica of glyphosate
• Poly(o-methoxyaniline) modified electrode for detection of lithium ions
• Synthesis of Poly(Vinylferrocene) Perchlorate/Poly(3,3’-Diaminobenzidine) Modified Electrode in Dichloromethane for Electroanalysis of Hydroquinone
• Electrochemical behavior of hydroquinone and catechol at a silsesquioxane-modified carbon paste electrode