Precise design and synthesis of an AIE fluorophore with near-infrared emission for cellular bioimaging

Organic fluorophores emerge as important stains for bioimaging and biosensing, especially for fluorophores with aggregation-induced emission characters. However, the development of organic fluorophores with efficient AIE properties expand to far-red and/or near-infrared is still a great challenge. Herein, we precisely design and synthesize a novel D-π-A type of near-infrared AIE fluorophore (TPE-PTZ-R) by introducing phenothiazine (PTZ) to modify the typical AIE unit (tetraphenylethylene, TPE). TPE-PTZ-R displays good optical properties including a large Stokes shift and typical AIE properties. We next fabricate the uniform and stable AIE nanoparticles by loading Pluronic F127 and apply it in cellular bioimaging with high uptake efficiency, low cytotoxicity and good photostability.