Artigo
Manganese Phthalocyanine as a Biomimetic Electrocatalyst for Phenols in the Development of an Amperometric Sensor
Fecha
2009-01-01Registro en:
Journal of The Brazilian Chemical Society. São Paulo: Soc Brasileira Quimica, v. 20, n. 6, p. 1180-1187, 2009.
0103-5053
10.1590/S0103-50532009000600025
S0103-50532009000600025
WOS:000268336800025
S0103-50532009000600025.pdf
2933194342093387
Autor
Universidade Federal do Maranhão (UFMA)
Universidade Estadual Paulista (Unesp)
Univ Fed Vales Jequitinhonha & Mucuri
Universidade Estadual de Campinas (UNICAMP)
Inst Nacl Ciência & Tecnol Bioanalit
Resumen
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.