Chem. Commun., 2025, Accepted Manuscript DOI: 10.1039/D5CC04607F, Communication Xue Wu, Lingling Cao, Qiuyue Zhao, Junjie Kou, Ying Li, Fanpeng Kong, Bo Tang We developed DHX-Biotin-V, an NIR fluorescent probe that selectively detects viscosity with minimal interference from polarity or pH. It targets biotin receptors to enter tumor cells, where its fluorescence activates...