A novel porphyrin-based near-infrared fluorescent probe for hypochlorite detection and its application in vitro and in vivo

Reactive oxygen species (ROS), especially HOCl/ClO−, have been demonstrated to play essential roles in both physiological and pathological processes, and an abnormal level of HOCl/ClO− is related to some diseases. In this work, a very fast responsive (within 30 seconds) porphyrin-based fluorescent probe, TPP-TCF, for ClO− with a NIR emissive wavelength was prepared. This probe exhibited excellent selectivity towards ClO− and would not be interfered with by other ROS and typical nucleophiles. The limit of detection (LOD) for ClO− was evaluated to be 0.29 μM, indicating high sensitivity towards ClO−. In further bioimaging experiments, TPP-TCF displayed low-cytotoxicity and good cell penetrability for recognizing exogenous ClO− in HeLa cells. Moreover, this probe was successfully applied in imaging endogenous ClO− in living animals.