A NIR Dual-Channel Fluorescent Probe for Fluctuations of Intracellular Polarity and H2O2 and Its Applications for the Visualization of Inflammation and Ferroptosis

Hydrogen peroxide and polarity are closely related to many physiological activities and pathological processes. However, near-infrared fluorescent probes that are sensitive to both H₂O₂ and polarity are still scarce. Herein, we developed the first dual-channel near-infrared fluorescent probe NBO, with an AIE effect, enabling simultaneous monitoring of H₂O₂ and polarity. The probe presented high sensitivity, high selectivity, and low detection limit for H₂O₂. It also had high sensitivity to polarity, independent of pH and viscosity, with large Stokes shifts, good photostability, and low cytotoxicity. Moreover, NBO was able to detect both endogenous and exogenous H₂O₂ as well as polarity fluctuations in vivo as a method to effectively differentiate between cancer cells and normal cells. Importantly, it also could monitor the therapeutic effects of drugs in inflammation and iron-dead cells and mice. Based on NIR emission, NBO could be used as an imaging tool and a way to evaluate the therapeutic effect of drugs for inflammation and ferroptosis.