Design strategy of multifunctional and high efficient hydrogen sulfide NIR fluorescent probe and its application in vivo

With the improvement of organic synthesis technology and the development of fluorescent probe, more and more fluorescent probes with excellent performance and versatility are required, so as to better realize their application value. High sensitivity, high selectivity, targetable and fast response NIR fluorescence probes are still needed for hydrogen sulfide precise detection. In this study, phenol containing 2, 4-dinitro group was selected as a strong electrophilic group to promote the nucleophilic substitution reaction. After the nucleophilic addition reaction between probe and hydrogen sulfide with delicate structure, strong nucleophile, 2, 4-dinitrophenol departure quickly and the NIR fluorophore was released, which showed fluorescence emission at 741 nm, and the probe detection limit for hydrogen sulfide was calculated as 96 nM. Interestingly, because of the positive charge in the hemiocyanine, the probe can locate efficiently in the mitochondria. This fluorescent probe with excellent performance was used to detect the endogenous levels of hydrogen sulfide in vivo. This work provides guidance for the design of multifunctional and high-performance fluorescent probes.