Simultaneous Discrimination of Hypochlorite and Single Oxygen during Sepsis by a Dual-Functional Fluorescent Probe

Hypochlorite (ClO–) and singlet oxygen (1O2) commonly coexist in living systems and exert important interplaying roles in many diseases. To dissect their complex inter-relationship, it is urgently required to construct a fluorescent probe that can discriminate ClO– and 1O2 in living organisms. Herein, by taking the 3-(aliphaticthio)-propan-1-one group as the unique recognition unit for both ClO– and 1O2, we proposed the first fluorescent probe, Hy-2, to simultaneously discriminate ClO– and 1O2 with high sensitivity and selectivity. Probe Hy-2 itself showed fluorescence in blue channel. After treatment with ClO– and 1O2, respectively, pronounced fluorescence enhancements were observed in the green channel and red channel correspondingly. Moreover, upon development of the probe with aggregation-induced emission (AIE) characteristics, the probe could work well in a solution with high water volume fraction. Probe Hy-2 was also able to accumulate into mitochondria and was utilized as an effective tool to image exogenous and endogenous ClO– and 1O2 in mitochondria. Significantly, as the first trial, probe Hy-2 was employed to simultaneously monitor the variation of ClO– and 1O2 level in cecal tissues of rat in the cecal ligation and puncture (CLP)-induced polymicrobial sepsis model. The results demonstrated that the expressed ClO– and 1O2 levels were tightly correlated with the severity of sepsis, inferring that the overproduction of ClO– and 1O2 is an important factor in the pathogenesis of sepsis. The probe illustrated herein may provide a guide for further exploring the functions of ClO– and 1O2 in various diseases.