The detection of trace uranium in water is essential for mitigating health risks associated with uranium exposure. Electrochemical detection presents a promising and efficient approach for the rapid, real-time monitoring of trace uranyl ions (UO?2?) in aqueous environments.

This study aims to utilize the high specific surface area and the hybridization ability of the surface orbitals of antimonene (AM), a two-dimensional material, to load oligonucleotides on the surface of AM by self-assembly method, and to be used as a specific uranyl ion probe for the electrochemical detection of trace uranium in water.

First of all, test samples consisted of Uranyl ion (UO₂²⁺), Oligonucleotide, AM, etc., were prepared according to strict processing steps. Then, atomic force microscopy (AFM) and ultraviolet absorption spectroscopy (UVAS) were employed to observe and confirm the successful loading of oligonucleotides on the antimonene surface. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) scans were applied to testing that AM-loaded oligonucleotides were less internally resistive and more electrochemically active than individual oligonucleotides or AM. The effects of electrode modification density, temperature, pH, and enrichment time on the detection performance of uranyl ions were further explored using differential pulse voltammetry (DPV) tests. Finally, the sensitivity, specificity, and stability of the electrochemical sensors based on AM-loaded oligonucleotide probes were evaluated.

Test results show that the detection conditions are optimized using the DPV method, and the optimal conditions are found to be a modifier concentration of 0.8 mg?mL^-1, an electrolyte pH of 3.0, a temperature of 30 ℃, and an incubation time of 12 min. Under the optimized conditions, the linear range is 1.48×10^-8~1.07×10^-7 mol?L^-1, and the detection limit is 2.99×10^-10 mol?L^-1, along with good reproducibility, selectivity, and reliability for real-water detection.

A novel strategy for constructing high-performance electrochemical sensors for uranyl ion detection using oligonucleotides proposed in this study presents an innovative probe material design scheme to enable the development of simple, efficient, and flexible electrochemical uranyl sensors for practical applications.