A novel carbopyronin-based mitochondria-targeting fluorescent probe for highly reactive oxygen species and its application in living cells and zebrafish.

Highly reactive oxygen species (hROS) are very important biological mediators, which are closely related to many physiological processes and diseases. Although fluorescent probes are one of the widely used detection tools for hROS in clinical practice, there are still challenges such as short wavelengths, and detection for a single species. Therefore, we focused our research on the development of long-wavelength fluorescent probes for multiple hROS detection to enable sensitive diseases diagnosis. In this paper, we presented a novel mitochondrial targeting fluorescent probe, DMA-Bpin, by one-step synthesis based on carbopyronin dye and boronate reaction sites. DMA-Bpin demonstrated exceptional sensing capabilities, featuring rapid response (within 10 min), visual colour change (from colorless to blue) and high sensitivity (detection limits of 1.5 nM for HOCl and 3.6 nM for ONOO). In addition, DMA-Bpin effectively detected low levels of hROS in HeLa cells and zebrafish. Furthermore, DMA-Bpin could not merely screen cancer cells but track the fluctuations of hROS in ferroptosis models. Therefore, DMA-Bpin is expected to become a new tool for tumor diagnosis and evaluation of treatment process. Equally important, we further found that the reaction of DMA-Bpin with hROS generated a new dye, DMA-OH. It not only exhibits many unique spectral properties, but also features simple synthesis and a modifiable reaction site. Thus, we provide a simple synthetic strategy to use DMA-OH as a novel fluorophore for developing diverse long-wavelength probes to detect various analytes.