Manganese phthalocyanine as a biomimetic electrocatalyst for phenols in the development of an amperometric sensor

• Autor(a) principal: Santos,Wilney de Jesus R.
• Data de Publicação: 2009
• Outros Autores: Sousa,Aline L., Sotomayor,Maria del Pilar T., Damos,Flavio S., Tanaka,Sônia Maria C. N., Kubota,Lauro T., Tanaka,Auro A.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Journal of the Brazilian Chemical Society (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532009000600025
• topic: manganese phthalocyanine; phenolic compound; amperometric sensor

The construction of an amperometric sensor for phenolic compounds using a carbon paste electrode modified with manganese phthalocyanine and histidine is reported. Under optimized conditions, at 0 mV vs Ag/AgCl in 0.1 mol dm-3 phosphate buffer solutions (pH 7.0) containing 250 µmol dm-3 H2O2, a linear response for catechol from 20 up to 130 µmol dm-3 was obtained with a sensitivity of 0.56 (± 0.02) µA dm³ µmol-1 cm-2. The detection limit was 1.1 µmol dm-3 and the response time was 2 s. The sensor presented stable response during 40 successive determinations. The repeatability, evaluated in terms of relative standard deviation, was 3.6% for n = 5 and [catechol] = 10 µmol dm-3. The sensor responses for other phenolic compounds were also investigated in details. Finally, the applicability of the sensor was tested in a pharmaceutical containing dopamine and the results compared favorably with those obtained with the official method.