Porous Organic Cages with Aggregation-Induced Emission Property for Anti-counterfeiting Ink Bioimaging

The application of aggregation-induced emission (AIE) materials in biological imaging holds multiple significances, including improving detection sensitivity and specificity, optimizing the imaging process, expanding the scope of application, and promoting advancements in biomedical research. In this work, the propeller ligand was constructed through McMurry coupling reaction and Suzuki coupling reaction by using dimethoxybenzophenone as the starting material. Then, an imine condensation reaction was carried out in chloroform solution, using a 3:2 molar ratio of precursor to tri(2-aminoethyl) amine to synthesize C₃ symmetric porous organic cage C_B. The structures of the compounds were determined by nuclear magnetic resonance spectroscopy (NMR), electrospray ionization mass spectrometry (ESI-MS) and Fourier transform infrared spectroscopy (FT-IR). The optical investigation results reveal that ligand L–B and the porous organic cage C_B demonstrate remarkable aggregation-induced emission (AIE) properties in a tetrahydrofuran/water mixed solvent system, along with a pronounced response to tetrahydrofuran vapor stimuli. Consequently, Furthermore, given its unique cage-like structure, high quantum yield, and outstanding AIE behavior, the porous organic cage C_B holds promise for applications in cell imaging.