Chelating and Construction Effects on a Self‐Assembled Blend for Electrochemical Lead (II) Detection

Abstract

This work presents a study of self-assembled platforms of polyelectrolytes constructed by drop casting on screen-printed electrodes for lead (II) sensing. Infrared characterization by attenuated total reflection (ATR) and electrochemical impedance spectroscopy (EIS) were carried out to evaluate the modification of the surface, its stability against treatment and the changes induced by the adsorption of lead cations. An equivalent circuit of the type R1 [R2 CPE1] CPE2 that explained the results for the actual surface modification was obtained. Linear correlations with lead concentration in the range of 0.5–2.5 mm were found by differential pulse voltammetry (DPV) and EIS techniques for solutions at pH 3. There was a particular concentration in which the presence of citrate increased the DPV reduction signal of lead while ethylenediaminetetraacetic acid (EDTA) diminished it.