Intracellular Self-assembly of TPE-biotin Nanoparticles Enables Aggregation-Induced Emission Fluorescence for Cancer-Targeted Imaging

Fluorogens with aggregation-induced emission (AIE) characteristics have recently been widely applied for studying biological events, and fluorogens with "smart" properties are especially desirable. Herein, we rationally designed and synthesized a biotinylated and reduction-activatable probe (Cys(StBu)-Lys(biotin)-Lys(TPE)-CBT (\textbf1)) with AIE properties for cancer-targeted imaging. The biotinylated probe \textbf1 can be actively uptaken by the biotin receptor-overexpressing cancer cells, and then "smartly" self-assemble into nanoparticles inside cells and turn the fluorescence "On". Employing this "smart" strategy, we successfully applied probe \textbf1 for cancer-targeted imaging. We envision that this biotinylated intelligent probe \textbf1 might be further developed for cancer-targeted imaging in routine clinical studies in the near future.