An amphiphilic fluorogen with aggregation-induced emission characteristic for highly sensitive and selective detection of Cu2+ in aqueous solution and biological system

Fluorescent sensor has demonstrated to be a facile and effective method to detect heavy metal ions owing to its unique characteristics such as simplicity, ease of operation and cost-effectiveness. In this work, a novel fluorescent probe with aggregation-induced emission (AIE) feature that contains an amide ligand base on the tetraphenylethylene (TPE) dye was designed and successfully synthesized. The utilization of the AIE-active fluorescent probe (named as FDPA) for detection of Cu2+ in aqueous solution has also been examined. We demonstrated that the resultant AIE-active molecule displays amphiphilic property and can self-assemble in aqueous solution with remarkable enhancement of fluorescent intensity owing to its AIE feature. The detection limit of probe for Cu2+ determination is 6.11 × 10−9 M and shows excellent selectivity in the presence of competitive ions. This work provides a useful route to overcome the fluorescence quenching of conventional fluorescent probes in aqueous solution and an elegant way to prepare fluorescent probes with better fluorescence properties.