Cation–anion interaction-directed formation of functional vesicles and their biological application for nucleus-specific imaging

A strategy for construction of counterion-induced vesicles in aqueous media has been described using imidazolium salts with multiple imidazolium moieties and alkyl carboxylate counteranions. The spontaneous formation of vesicles can be achieved by the simple selection of the counteranion to satisfy the requirement of the packing parameter for vesicle formation. Functional fluorescent vesicles can also be formed by the introduction of an aggregation-induced emission (AIE) fluorophore, tetraphenylethene (TPE), as the core of the imidazolium salt TPEI-C8, which also exhibits highly specific nucleus imaging in living cells. Considering the distinct AIE characteristic of TPEI-C8, the aggregation-induced strong fluorescence emission of TPEI-C8 in the cell nucleus may be the main reason for the specific fluorescence images of the cell nucleus. The strategy for the construction of functional vesicles reported in this study has shown great potential for the construction of other functional vesicles.