Based On The Detection Of Azo Reductase And Hydrogen Peroxide Fluorescent Probe Synthesis, Properties And Biological Imaging Research

In the process of cell growth,proliferation and apoptosis,bioactive enzymes are involved in every step.Small molecules within the cell,including reactive oxygen species and metal ions,play essential roles in cell signaling for regulating a variety of biological processes.Intracellular enzyme reactions and small molecule abnormal may lead to dysfunction and problems of cell function,increasing the risk of disease.Studying these substances are important for monitoring cell function and preventing disease.In recent years,fluorescent probes with high sensitivity and specificity have been used in the field of biochemistry and medicine,becoming a research hotspot.Based on the pharmacological effects and fluorescence characteristics of camptothecin,a camptothecin derivative SN-38 was used as a fluorophore to design and synthesize a fluorescent probe ARP-1 for detecting azo reductase and targeting hypoxia tumors.After adding coenzyme NADH and rat liver microsomes,spectra properties of ARP-1 were recorded in DMSO:HEPES?1:9,pH=7.2?system.ARP-1is capable of releasing the active drug SN-38 at 560 nm emits strong fluorescence signal,the physical appearance also changed from pale blue to green fluorescence.The fluorescent imaging experiments show that ARP-1 can release SN-38 in the cell and nematode of the hypoxic state.The therapeutic potential of ARP-1 for both tumor-specific localization and suppression of tumor weights was validated in xenograft mouse model.It is a low oxygen probe with good selectivity and sensitivity.The design and synthesis three probes HP1,2 and 3 based on naphthalimide for detecting hydrogen peroxide.The spectral properties were tested in DMF:PBS?2:8,pH=7.4?system.It is found that compound react with hydrogen peroxide from blue fluorescence at 450 nm to yellow-green fluorescence at 550 nm.Then HP1 was applied to biological imaging,show that HP1 can detect the hydrogen peroxide in vivo.Afterwards,the synthesize a near-infrared probe RHP1 using aresazurin sodium salt as the fluorophore.In the same solvent conditions,the spectroscopic properties of RHP1were tested.The absorption peak of RHP1 between 390 nm⁶50 nm.The initial fluorescence of RHP1 is weak.After adding hydrogen peroxide,the absorption peak between 390 nm⁵48 nm is decreased,but 548 nm⁶50 nm is increased.The physical appearance also changed from blue to pink.The addition of H₂O₂ to RHP1 leads to an increase in the fluorescence intensity at?em=639 nm by about 15 fold.Then RHP1was applied to cell and C.elegans imaging,showed that RHP1 is a near-infrared fluorescent probe which can detect exogenous and endogenous of hydrogen peroxide.