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 Taboada [UNESP], Damos, Flavio S., Tanaka, Sonia Maria C. N., Kubota, Lauro T., Tanaka, Auro A.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1590/S0103-50532009000600025; http://hdl.handle.net/11449/40268
• 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 mu mol dm(-3) H2O2, a linear response for catechol from 20 up to 130 mu mol dm(-3) was obtained with a sensitivity of 0.56 (+/- 0.02) mu A dm(3) mu mol(-1) cm(-2). The detection limit was 1.1 mu mol 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 mu mol 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.