Detection of uranium with a wireless sensing method by using salophen as receptor and magnetic nanoparticles as signal-amplifying tags

作者:Yang, Miao; Liao, Lifu*; Zhang, Guangliang; He, Bo; Xiao, Xilin; Lin, Yingwu; Nie, Changming
来源:Journal of Radioanalytical and Nuclear Chemistry, 2013, 298(2): 1393-1399.
DOI:10.1007/s10967-013-2663-z

摘要

A new wireless sensing method for the detection of uranium in water samples has been reported in this paper. The method is based on a sandwich-type detection strategy. Salophen, a tetradentate ligand of uranyl ion, was immobilized on the surface of the polyurethane-protected magnetoelastic sensor as receptor for the capture of uranyl ion. The phosphorylated polyvinyl alcohol coated magnetic Fe3O4 nanoparticles were used as signal-amplifying tags of uranyl ion. In a procedure of determining uranium, firstly uranyl ion in sample solution was captured on the sensor surface. Then the captured uranyl bound the nanoparticle through its coordination with the phosphate group. The amount of uranium was detected through the measure of the resonance frequency shift caused by the enhanced mass loading on the sensor surface. A linear range was found to be 0.2-20.0 mu g/L under optimal conditions with a detection limit of 0.11 mu g/L. The method has been applied to determine uranium in environmental water samples with the relative standard deviations of 2.1-3.6 % and the recoveries of 98.0-101.5 %. The present technique is one of the most suitable techniques for assay of uranium at trace level in environmental water samples collected from different sources.