Emission‐Tunable Nanofluorophores through Self‐assembly of Amphiphilic Block Copolymers: toward Application in Cell Imaging

Comprehensive Summary Nanofluorophores based on aggregation‐induced emission (AIE) dyes have recently received considerable attention because of their unique optical properties and biocompatibility. In this work, we report an emission‐tunable nanofluorophore constructed by the self‐assembly of an amphiphilic block copolymer (denoted by PTN). The diblock copolymer was synthesized by RAFT polymerization. A polyethylene glycol‐based trithiocarbonate was employed as the macromolecular chain transfer agent, and a near‐infrared emitting tetraphenylethylene derivative with a vinyl terminal group was designed as the monomer. The block copolymers self‐assembled in an aqueous solution to form nanospheres, which showed near‐infrared emission at approximately 720 nm with a significant Stokes shift of approximately 260 nm. Furthermore, nanofluorophores have excellent biocompatibility, photostability, and pH‐independent emission‐tunable properties, and were successfully applied to label HeLa cells for fluorescence imaging. The diblock copolymers formed spherical nanoparticles through flash precipitation, which showed fluorescence emission at approximately 720 nm and a significant Stokes shift of approximately 260 nm. The nanoparticles were successfully applied to label HeLa cells for fluorescence imaging.