Design And Imaging Study Of Long-wavelength Fluorescent Probes For Biological Reactive Oxygen Species

Reactive oxygen species are a general term for active substances containing oxygen,mainly including peroxynitrite(ONOO^-),hypobromous acid(HOBr),hypochlorous acid(HOCl),hydrogen peroxide(H₂O₂),superoxide anions(O₂^·-),singlet oxygen(¹O₂)and hydroxyl radical(·OH).Recent studies have found that reactive oxygen species play an important role in living organisms and are closely related to life activities such as cellular immunity,signal transduction and differentiation.When the concentration of active oxygen in the organism changes abnormally,it often causes oxidative damage to the organism.ROS is extremely difficult to detect due to its high chemical reactivity and short life.Therefore,in combination with the chemical reaction properties of reactive oxygen species,it is extremely important to design and develop novel chemical detection tools for the detection of reactive oxygen species in living organisms.This will help us to further study the physiological and pathological effects of reactive oxygen species,and will greatly assist in the diagnosis and treatment of related diseases.In this paper,three novel fluorescent probes were synthesized by reasonable molecular design,and they can detect in vitro and intracellular peroxynitrite(ONOO^-)and hypobromous acid(HOBr).(1)Based on the dicyanomethylenyl-4H-furan derivative and ICT mechanism,a novel far-red off-on fluorescent probe DCM-KA was designed to detect peroxynitrite in cells.The probe has excellent selectivity and sensitivity to ONOO^-with a response time of only 90 s and a minimum detection limit of 78 n M.At the same time,the probe has been successfully used for endogenous ONOO^-detection of mouse monocyte macrophage(J774A.1 cells).(2)A near-infrared on-off fluorescent probe DCSN for detection of hypobromous acid in cells was designed based on that HOBr will cause a coupling reaction between amino group and S-methyl group.The probe has good selectivity and sensitivity to HOBr with a minimum detection limit of 0.65?M.This probe has been used for the detection of hypobromous acid in human breast cancer cell(MCF-7 cells).(3)Based on the lysosomal targeting properties of morphine structures and naphthalimide-derived compounds,a first ratiometric fluorescent probe Lyso-Np SN for the targeted detection of hypobromous acid in lysosomes was designed.The probe has a minimum detection limit of 99 n M for HOBr and has good selectivity for HOBr.In addition,this probe has been successfully used for the detection of hypobromous acid in Hela cells lysosomes.