Evaluation and development of GO/UiO-67@PtNPs nanohybrid-based electrochemical sensor for invisible arsenic (III) in water samples

Invisible arsenic is a highly toxic pollutant in water bodies. Therefore, a quick, simple, eco-friendly, and sensitive detection method is significant for environmental governance, toxicological evaluation, and human health. A novel platform has been put forward to the determination of arsenic (As3+) in the real wastewater. The sensing platform was established on the basis of octahedral UiO-67 metal-organic framework (UiO-67 MOF) and Platinum nanoparticles (PtNPs). The UiO-67 MOFs had a porous structure with a great specific surface area, which was beneficial to the adsorption and concentration of arsenic. Graphene oxide (GO) can be accelerated electron transfer and increased abundant active sites, while platinum nanoparticles (PtNPs) can be facilitated the selective recognition of As3+ due to their electrocatalysis. The electrochemical properties of the GO/UiO-67@PtNPs composites were studied. Under optimized conditions, the GO/UiO-67@PtNPs sensors can be applied to the ultrasensitive and selective monitoring of As3+ in an aqueous solution, and exhibited high electrochemical performance toward As3+, including a wider linear range of 2.7-33.4 nM, and a lower detection limit of 0.48 nM, which is lower than the safety standard of drinking water constructed by the World Health Organization (WHO, 10 mu g L-1). In addition, the developed sensing platform displayed excellent anti-interference, reproducibility, reliability, and applicability for the determination of As3+ in different environmental samples.

Automated summary

A novel platform based on UiO-67 MOF and PtNPs was developed for the detection of arsenic in wastewater. The platform exhibited high sensitivity, selectivity, and reliability, and could accurately monitor and measure arsenic in different environmental samples.