Tetraarylimidazole-Based Aggregation-Induced Emission Luminogens and Their Cell-Imaging Application

1,2,4,5-Tetraphenylimidazole takes a highly twisted propeller-like conformation, which results in its potential to be developed into aggregation-induced emission (AIE)-active molecules. Herein, two tetraarylimidazole-based aggregation-induced emission luminogens (TAI-m and TAI-q) were easily synthesized through a one-pot, four-component reaction in high yields. Their structures were fully characterized by nuclear magnetic resonance (NMR) and high-resolution mass spectra (HRMS). Furthermore, the crystal structures of them confirmed their highly twisted conformation. Both TAI-m and TAI-q exhibited good AIE properties. The self-aggregation nanoparticles and the pluronic F-127 encapsulated nanoparticles of them were prepared for comparative study of their cell imaging performance. The findings indicated that they showed the distinct staining behaviors. The cells stained with the self-aggregates showed clear cell outlines but fuzzy cell interiors. By comparison, the pluronic F-127 encapsulated nanoparticles can be distributed in the whole cell.