Self-assembled aggregation-induced emission micelle (AIE micelle) as interfacial fluorescence probe for sequential recognition of Cu2+ and ATP in water

Abstract

Cu2+ ions and adenosine-5′-triphosphate (ATP) play important roles in the process of cellular metabolism, building artificial chemosensor for detecting them are of great significance. In this work, on the basis of a tetraphenylethylene (TPE) amphiphile (1) which can generate the aggregation-induced emission (AIE) micelles through self-assembling in aqueous solution, we developed a new interfacial system for sequential recognitions of Cu2+ and ATP with high selectivity and sensitivity. Once Cu2+ was introduced into the 100% aqueous solution of probe 1, a complex composed by the probe and Cu2+ with a 1:2 stoichiometry was formed, leading to remarkable fluorescence quenching. Adding ATP to the solution of the in situ generated 1-Cu2+ ensemble can easily recover the fluorescence of the system. The limits of detection (LoD) for Cu2+ and ATP were calculated to be 1.0×10−7 and 1.5×10−6M. Both 1 and the resultant 1-Cu2+ complex were demonstrated to have low cytotoxicity and good cell-membrane permeability, they were successfully applied to image Cu2+ ions and ATP in living HepG2 cells.