Covalent Bond Locking in Semiconducting Oligomers Boosts Ultrabright NIR-II Luminescence for Deep Brain Theranostics.

Near-infrared (NIR)-II fluorescence imaging at 1000-1700 nm is widely used for deep-tissue visualisation and disease theranostics in the brain, with NIR-II theranostics greatly improving imaging resolution, imaging depth, and therapeutic efficacy. However, the extreme lack of molecular design in NIR-II fluorophores has slowed the discovery of bright candidates and restricted their efficacious application in brain theranostics. Here, we develop a covalent bond locking (CBL) strategy that enables ...