Dimethylglyoxime modified screen-printed electrodes for heavy metals determination

Abstract

Heavy metals concentration has increased due to the anthropogenic activity. As a consequence, higher concern about their potential effects on the human health and the environment has grown as they are systemic toxicants known to induce multiple organ damage, even at very low concentrations. Consequently, the contamination of natural or drinking water by heavy metals supposes a significant threat to natural ecosystems and human health, requiring methods that allow their determination and monitoring at low concentrations. Particularly, nickel is a common industrial pollutant found in wastewater, contaminated soils and in the air around industrial areas .Nickel toxicity in humans has received important attention due to the carcinogenic character of this element. The conventional methodology for the determination of heavy metals is based on the use of atomic spectroscopic techniques. However, these systems are expensive, bulky and require qualified personnel capable of carrying out the analyses. In addition, they do not usually allow the analysis of the samples on-site. For the on-site detection of heavy metals, electrochemical devices offer attractive possibilities to meet these needs. The advantages of electrochemical systems include high sensitivity and selectivity, high speed, a broad linear range, compatibility with modern micro fabrication techniques, low energy and space requirements and low cost instrumentation. In addition, both the sensor and the instrumental part can be easily miniaturized to obtain compact portable devices that are easy to use on-site. In this regards, this work presents the development of a voltammetric sensor based on carbon screen-printed electrodes (SPCEs) chemically modified with dimethylglyoxime (DMG) for the determination of Ni(II) by adsorptive stripping voltammetry (AdSV). Developed sensors were analytically characterized in terms of sensitivity, selectivity, limits of detection and quantification, linear range, repeatability, reproducibility and durability. Lastly, the developed sensor was applied to the determination of Ni(II) in a certified wastewater sample