Sulfur-substituted hemicyanine-based NIR fluorescent probe for hypochlorous acid enables imaging of liver injury and plasma diagnosis of sepsis.

Hypochlorous acid (HClO), as a key reactive oxygen species in the human immune defense, can be found in tissue damage and bloodstream infections, which can serve as a biomarker for diagnosis of blood sepsis and drug-induced liver injury (DILI). Here, based on the advantages of NIR fluorescent probe, an HClO-activatable sulfur-substituted hemicyanine-based NIR fluorescent probe for imaging of drug-induced liver injury and plasma diagnosis of sepsis was developed in this paper. HClO-CyOH-S exhibits turn-on NIR fluorescence response towards HClO with an excellent selectivity and good sensitivity. HClO-CyOH-S has been successfully applied for the detection of endogenous and exogenous HClO in cells. Moreover, the probe was successfully applied for imaging and diagnosis of DILI. Finally, HClO-CyOH-S was successfully applied to plasma diagnosis of sepsis, achieving visual detection of sepsis. These results demonstrate that HClO-CyOH-S is a powerful tool for monitoring HClO in physiological environment, imaging and diagnosing liver injury, and visually detecting sepsis.