A Mitochondrial-targeted curcumin-based fluorescent probe for real-time tracking endogenous hydrogen peroxide in living cells

To explore high-performance fluorescent probes that endow tunability and capability for in vivo analysis is an enduring goal of visualizing and manipulating biological events. Hydrogen peroxide H2O2, as a central redox signaling molecule, is the tough hurdle to real-time in situ tracking dynamic subcellular H2O2. Herein, we present a curcuminoid difluoroboron based fluorescent probe DFB-1 which contains the triphenylphosphine (TPP) moiety as mitochondrial targeting unit and aryl boronates as the specific uncaging group. Notably, this activatable probe DFB-1 bestows several striking characteristics: (i) dual-channel fluorescence response with a large shift; (ii) active mitochondria-targeting; (iii) light-up NIR fluorescence with high signal-to-background ratio. The probe DFB-1 is successfully employed in sensing endogenous H2O2 with a limit of detection 0.025 & mu;M, and effectively differentiate H2O2 fluctuation between hepatocellular carcinoma and colorectal cancer cells. This dual-channel NIR probe DFB-1 realizes new advances in deep insight into the function of mitochondrial endogenous H2O2.

Automated summary

In this study, a novel fluorescent probe DFB-1 was synthesized which showed dual-channel fluorescence response, mitochondria-targeting ability, and high signal-to-background ratio. DFB-1 could track and differentiate the fluctuation of endogenous H2O2 in hepatocellular carcinoma and colorectal cancer cells. This probe provides new insights into the function of mitochondrial endogenous H2O2.