Electrochemical determination of heavy metal ions applying screen-printed electrodes based sensors. A review on water and environmental samples analysis

Heavy metals are pollutants characterized by non-biodegradability and toxicity above certain thresholds for both, human health and environment. In this scenario, analytical tools able to guarantee in-situ, fast, sensitive and selective determination of such contaminants is becoming a priority to meet the needs of environmental quality standards determined by relevant regulations. Electroanalytical devices based on the use of screen -printed electrodes (SPEs) could play a key role in the transition from standard laboratory analytical tech-niques to portable low-cost sensors. Here, we review electroanalytical tools for metal ions determination in water and environmental samples based on the use of screen-printed electrodes, focusing the attention on both, custom-made and commercially available SPEs solutions. It was pointed out as the performance reached, in most of the cases, combined with characteristics like the portability, low cost and facile analysis, result enough to justify their potential as reliable alternative to conventional spectroscopic techniques. On the other hand, for the se-lective and simultaneous determination of different target metal ions in complex environmental matrixes, a key role is played by the concentration ratios among target and interfering metal ions, requiring for further re-searchers effort to satisfactorily address this challenge.