Multicenter-Emitting Carbon Dots: Color Tunable Fluorescence and Dynamics Monitoring Oxidative Stress In Vivo

To date, dynamics monitoring oxidative stress on time resolution in vivo has not been achieved due to the limitation of probes, causing the difficulty to comprehensively understand its biological behaviors and functions. Herein, we propose a novel probe, namely highly bright and color tunable "multicenter-emitting" carbon dots (C-dots), for dynamics monitoring oxidative stress in vivo. Combined with experiments and theoretical calculations, we reveal that each C-dot contains multiple conjugated polyaromatic units on their surfaces, which act as fluorescent emitting centers and response sites of hypochlorous acid (HClO) to achieve an instantaneously color-change readout (107 nm, from yellow-green to blue). Accordingly, the proposed C-dots enable the observation of HClO burst and dynamics evolution at fresh wounds of zebrafish larvae. Such a burst occurs only at 1–5 s after cutting, which is an unprecedented thought regarding oxidative stress dynamics. Furthermore, the present study indicates that HClO molecules are principally generated in situ rather than migration.