Visualized uranium rapid monitoring system based on self-enhanced electrochemiluminescence-imaging of amidoxime functionalized polymer nanoparticles

The development of uranyl ion detection technology has exhibited its significance in public security and environmental fields for the radioactivity and chemical toxicity of uranyl ion. The WHO standard of uranyl ion makes it necessary to develop highly sensitive uranyl rapid warning system in drinking water monitoring. Herein, a visualized rapid warning system for trace uranyl ion is carried out based on electrochemiluminescence (ECL) imaging technology to give an ultra-low limit of detection (LOD) and high selectivity. Amidoxime, a bi-functional group with both uranyl ion capturing and co-reactive functions, is modified on a conjugated polymer backbone with strong ECL signal to be prepared into three-in-one polymer nanoparticles (PNPs) with self-enhanced ECL property. The captured uranyl ion can enhance the ECL signal of PNPs via resonance energy transfer process to give the LOD as 0.5 ng/L, which is much lower than the known luminescent uranyl sensors. Furthermore, ECL imaging technology is introduced into realizing visualized uranyl rapid warning, and can be successfully applied on natural water samples. This study provides a novel strategy for uranyl rapid warning, and shows its potential meaning in public security and environmental fields.