Eletrodo de ouro como sensor eletroquímico para monitoramento de chumbo em águas naturais para abastecimento público

Abstract

Potentially toxic metals could bioaccumulate in body tissues of living organisms and can cause toxicological effects on soil properties and human and animal health. There are several methodologies available for the quantification of metals in aqueous matrices. However, these techniques become expensive due to the high cost and the need for specialized professionals to handle the equipment. Therefore, the objective of this work was the application of the gold electrode (EAu) without modifications on its surface in order to analyze the presence of Pb2+ ions in surface waters of Córrego Lanoso in Uberaba - MG, through anodic stripping voltammetry, without the need for sample preparation. The voltammetric parameters were optimized with the aid of the Rotational Central Composite Design (DCCR) and the validation of the method was performed using an atomic emission spectrophotometer (MP-AES 4200 Agilent). The analyzes using the electrochemical sensor showed limits of detection (LD) of 0.04 ng L-1 and limit of quantification (LQ) of 0.13 ng L-1. Furthermore, lead levels were found in the real sample, evidencing the effectiveness of using the EAu without modifications, to detect Pb2+ ions in natural waters (public supply). In short, this methodology proved effective in quantifying Pb2+ ions in concentration in the environment, easy handling, real-time analysis, without the need for sample preparation, leaving only economic feasibility studies for the commercial implementation of the aforementioned electrochemical sensor.