Studies based on the electrochemical response of 2-(2-nitrophenyl)-1H-benzimidazole at chemically modified electrodes with over-oxidized poly-1-naphthylamine

M.MORESSI*; H.FERNÁNDEZ; M.A.ZÓN; A.H.ARÉVALO; L.E.SERENO; A.ALVAREZ-LUEJE; F. DERAMO

ELECTROCHIMICA ACTA

Elsevier

Lugar: Holanda; Año: 2010 vol. 55 p. 4424 - 4427

0013-4686

The development of a simple and efficient method to 2-(2-nitrophenyl)-1H-benzimidazole (NB) electrochemical determination using a polymer film coated chemically modified electrode is described. A glassy carbon (GC) electrode was modified employing an electro-polymerized film of 1-naphtylamine (1-NAP)followed by an over-oxidation treatment in 0.2M sodium hydroxide solution (poly-1-NAPox electrode).The electrochemical behaviour of NB at the poly-1-NAPox electrode was investigated in a mixture of 10% ethanol + 90% buffer solution (pH 2) by cyclic voltammetry (CV) and square-wave voltammetry (SWV). The experimental results suggested that the poly-1-NAPox electrode had a good effect on NB electrochemical response because it avoided the electrode surface fouling as a consequence of the adsorption of NB reduction products, which was found when a bare GC electrode was employed as the working electrode. The NB cathodic current was dependent on the polymeric film over-oxidation degree (˛).NB could be determined in the range from 2×10−6 to 5×10−5 M. The NB detection and quantification limits were 5×10−7 and 1.7×10−6 M, respectively. The percent relative standard deviation of the peak current to 10-replicated measurement using 1.2×10−5M NB solution was 1.4%. The method showed to be rapid, simple and with a good sensitivity.