Novel fluorescent chemosensor sensitively detect copper (II) through the collaboration of quinoline and coumarin groups

Copper ion (Cu2+) plays important role in life system and industry; therefore, efficient detection of Cu2+ is very important. To improve the selectivity and sensitivity of Cu2+, herein, quinoline and coumarin groups were rationally employed into a novel fluorescent sensor CQ to efficiently sensing Cu2+ through the collaboration of these two groups. Interestingly, the CQ possesses aggregation-induced emission (AIE) properties and shows nice selective and sensitive fluorescent response to Cu2+. The lowest limit of detection (LOD) for Cu2+ is 2.81 x 10(-8) M. Moreover, the Cu2+ sensing process has good anti-interference properties. The possible recognition mechanism was investigated by experiments and theoretical calculations, which supplied a deep insight not only on the collaboration of the quinoline and coumarin groups in the Cu2+ recognition process but also on the charge transfer induced fluorescent response mechanism. The results show that the CQ could specifically detect Cu2+ via the collaboration of the quinoline and coumarin groups through multiple coordination interactions. Importantly, test strips based on CQ were fabricated, which could act as test kits for convenient and efficient detection of Cu2+.

Automated summary

In this study, a new fluorescent sensor CQ was designed to efficiently sense Cu2+ through the collaboration of quinoline and coumarin groups. CQ showed selective and sensitive fluorescent response to Cu2+ with aggregation-induced emission properties. Experiments and theoretical calculations revealed the coordination interactions of quinoline and coumarin groups, as well as the fluorescent response mechanism.