Eletrodo de pasta de carbono modificado com ftalocianina de ferro(II) para determinação simultânea de carbendazim e naftol em suco de frutas

Abstract

In this study, carbon paste electrodes modified with cobalt, copper, iron, nickel, and zinc phthalocyanines were fabricated to compare the electroanalytical response of carbendazim (CBZ) and 1-naphthol (NAF), the main metabolite of carbaryl (CAR). CBZ and NAF are considered endocrine disruptors with potential carcinogenic effects, according to the United States Environmental Protection Agency (USEPA). Thus, a simple, selective, sensitive, rapid, and low-cost voltammetric method for the simultaneous determination of CBZ and NAF in orange and pineapple juices was developed by modifying the carbon paste electrode with iron phthalocyanine using cyclic voltammetry and square wave techniques. Additionally, a proposal for simultaneous voltammetric determination of CBZ and NAF using a batch-flow system was studied. The pH study in 0.10 mol L−1 Britton-Robinson buffer over the range of 1.80 to 10.0 was conducted, with pH 4.5 being chosen. Square wave voltammetry parameters were optimized, and the linear range of 49.80 to 244.0 nmol L−1 with limits of detection values of 0.59 and 1.80 nmol L−1, and limits of quantification between 0.72 and 2.40 nmol L−1, for CBZ and NAF respectively, were calculated. Precision study of the analytical method resulted in coefficients of variation less than 1,0 %. The standard addition method was employed to compensate for matrix effects in samples, yielding satisfactory recovery values between 82.8 % to 105.2 % and coefficients of variation below 2.0 %.