A Two-Photon Excited Near-Infrared Iridium(III) Complex for Multi-signal Detection and Multimodal Imaging of Hypochlorite.

Hypochlorite (ClO), as a type of reactive oxygen species (ROS), plays a crucial role in the process of oxidative stress and is closely related to many diseases. Thus, developing a method for detecting and imaging of ClO with high sensitivity and selectivity is of great significance. However, the applications of most luminescent probes are limited to the fact that the excitation and emission wavelengths of them are in the visible light region rather than in the near-infrared (NIR) region. Hence, an NIR iridium(III) complex () with two-photon excitation is designed for the detecting and imaging of ClO. In the presence of ClO, the luminescent intensity and lifetime of are remarkably enhanced. Interestingly, also exhibits excellent electrochemiluminescence (ECL) properties, and the ECL signal is significantly enhanced with the addition of ClO. What is more, is also suitable for the detection and analysis ClO by flow cytometry. Therefore, is developed to detect multiple signals and is successfully applied to detect exogenous and endogenous ClO in living cells with one-photon, two-photon, and phosphorescence lifetime image microscopy (PLIM). In addition, was successfully used for imaging of ClO in tissues and inflammatory mouse models. All of the above results indicate that is highly effective in detecting ClO in living systems.