A novel tetraphenylethene-based fluorescent sensor for uranyl ion detection with aggregation-induced emission character

Facile and efficient approaches for uranyl ion detection without tedious sample pretreatment and sophisticated instrumentation are in great demand in environmental monitoring and mitigation. In this work, a novel fluorescent sensor TPE-BSA with aggregation-induced emission (AIE) character was designed and synthesized for the uranyl ion detection, by incorporating salophen moiety into the AIE-active tetraphenylethene moiety. Fluorescence titrimetric studies revealed that TPE-BSA could detect uranyl ion in a simple way owing to the quenching of its aggregation-induced emission, with the limit of detection as low as 0.039 mu M. According to the results of particle size distribution analysis, H-1 NMR, Job's plot analysis, quantum chemical calculations and fluorescence lifetime measurement, the fluorescence quenching of TPE-BSA upon addition of uranyl ion could be ascribed to the complexation of TPE-BSA and uranyl ion as well as the heavy atom effect of uranyl ion. Furthermore, TPE-BSA was successfully used for the quantification of uranyl ion in drinking water, demonstrating that TPE-BSA has the potential to be employed in the detection of uranyl ion in the environmental system as an AIE-active sensor.