A Novel Aggregation-Induced Emission Material, CTRP With Red Emission Based on Coumarin Fluorophore

A novel aggregation-induced emission (AIE) material, CTRP, exhibiting red light emission was synthesized by integrating coumarin with triphenylamine through a Knoevenagel condensation reaction. This material demonstrates unique "on-off-on" optical switching behavior with its fluorescence intensity initially decreasing by 75% and then increasing by 450% as water content rises, highlighting its excellent AIE properties. CTRP also shows high sensitivity in detecting trace amounts of water, making it a promising fluorescent sensor for organic solvents. Unlike traditional tetraphenylethylene-based AIE materials, which typically emit blue light and pose risks of photodamage to biological tissues, CTRP's red light emission offers a safer and more biocompatible alternative. This advancement in long-wavelength AIE materials is expected to significantly expand their application scope particularly in biological systems enabling safer bioimaging, biosensing, and in vivo applications.