Síntese e caracterização de complexos metálicos para confecção de eletrodos modificados utilizados no estudo de antioxidantes

Abstract

The 3,4-(methylenedioxi) cinnamates complexes of Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II) were synthesized by stoichiometric addition of solutions of the sodium 3,4-(methylenedioxi) cinnamatein solutions of sulphate, chloride or nitrate of the respective metals. The synthesized compounds were characterized by thermogravimetry and differential thermal analysis simultaneous (TG-DTA), and the infrared spectroscopy (FT-IR). Through thermoanalytical techniques established the stoichiometric composition of each compound studied and with data of infrared suggest metal-ligand coordination mode. After characterization, the complexes were used as modifiers in the preparation of a carbon paste electrode modified, which were used to evaluate the performance in analytical applications. Thus, it was employed the cyclic voltammetry and linear sweep voltammetry, where some experimental and instrumental parameters were optimized. As the composition of paste, pH and supporting electrolyte and then used in the study of antioxidants propyl gallate and diphenylamine.