Detection of Lead(II) in Living Cells by Inducing the Transformation of a Supramolecular System into Quantum Dots
Yingjie Li, Tingting Huang, Juan Liu, Yongqiang Xie, Bingbing Shi, You‐Ming Zhang, Hong Yao, Tai‐Bao Wei, Qi Lin
Abstract
Due to the high toxicity of Pb2+, efficient in situ detection of Pb2+ is very important. Herein, a new approach for in situ probing of Pb2+ by inducing supramolecular systems to form fluorescent quantum dots (QDs) is demonstrated. At the beginning of this work, a new tetra-pillar[5]arene derivative was designed as host H. The H and an amphiphilic guest G could assemble into supramolecular systems in aqueous solution and form nanoparticles without fluorescence emission. Interestingly, S2– could crosslink the nanoparticles, changing them into fluorescent nanorods. Notably, the Pb2+ could induce these nanorods to in situ transform into PbS QDs; meanwhile, the system showed distinct fluorescent changes, and the fluorescence quantum yield of the system showed a dramatic increase. This in situ PbS QD formation process could be applied in efficient Pb2+ sensing in water and living cells. This research also provides a simple and feasible way to detect heavy metal ions by in situ construction of fluorescent nanomaterials and QDs through a supramolecular approach.