A ratiometric fluorescence mitochondrial-targeted probe for imaging HOCl in vitro and in vivo

HOCl, as one of reactive oxygen species, could cause tissue damage and induce various disease when it is at abnormal level or improper location. To monitor HOCl, we developed a near infrared ratiometric fluorescence probe C3H, which is capable to detect HOCl in real time. This probe gives two emission signals with no cross-talk in the process of monitoring HOCl, accompanied by a considerable variation (up to 348-fold) in its fluorescence intensity ratio (F480 nm/F750 nm). Additionally, probe C3H exhibited excellent properties such as fast response (<10 s), high sensitivity with a low detection limit (about 22.6 nM), high selectivity and anti-interference. Moreover, the probe possesses the capability of monitoring exogenous and endogenous HOCl in mitochondria. Finally, nude mouse imaging experiments show that the probe can detect exogenous ClO− in vivo.