Desenvolvimento de metodologia analítica baseada em eletrodo de carbono vítreo modificado com filme de bismuto: Aplicação em águas de chuva de regiões de Santa Catarina

Abstract

In this study an analytical methodology for determination of 2,4-dinitrofenol (2,4-DNP) in rainwater samples of regions of Santa Catarina was developed using the square wave voltammetry (SWV). The study involved the applicability to use the modified glass carbon electrode with bismuth film. The formation of the bismuth film was optimized by cyclic voltammetry and after that, studies of pH and electrolyte support were investigated for the reduction of 2,4-DNP (ex situ form). The analytical parameters that affect the sensitivity of the SWW were optimized. In order, the analytical figures of merit were obtained: linear working range of 3,2 × 10 -7 - 4,6 × 10 -6 mol L -1; excellent coefficient of correlation of 0,996; RSD% =17,5 (1,35 × 10 -6 mol L -1, n = 6), 11,7 (2,5 × 10 -6 mol L -1, n = 6) e 6,4 ( 4,6 × 10 -6 mol L -1, n = 6); limit of detection of 1,2 × 10 -7 mol L -1. Recovery studies were performed to evaluate the accuracy of the methodology. The values obtained were between 84 - 112% (2,7 × 10 -6 mol L -1 ) and 89 - 113% (4,3 × 10 -6 mol L -1).