Design,Synthesis And Properties Of Fluorescent Probes For Detection Of Bioactive Small Molecules

The active small molecules involved in many different kinds of life activities in vivo,and most of them exist in vivo,such as reactive oxygen species,reactive nitrogen species,biological thiols,and various active enzymes.And because of these biologically active molecules are more or less relate to same physiological and pathological processes in vivo,it plays a very important part for the keeping of various life activities and the production of various diseases.Therefore,the design of probes that can monitor their content and change process will be an important indicator for measuring various life processes in organisms,including cells.Based on the phenylborate moiety that can specifically recognize hydrogen peroxide,three certain similar structures fluorescent probes HOTZ-1,HOTZ-2 and HOTZ-3 for detecting hydrogen peroxide were synthesized in this paper.Spectroscopic tests evaluated with the condition of DMSO:PBS=3:7(p H=7.4)indicated that after HOTZ-1 reacted with H₂O₂,its about 30 times fluorescence intensity increased;while HOTZ-3 under the condition of DMSO:PBS=1:1(p H=7.8),after reacting with hydrogen peroxide under the condition,the fluorescence maximum emission is red-shifted from 580 nm to 680 nm,and the change is very significant.In the detection limit experiment of the two probes,the detection limit of HOTZ-1 was calculated to be 2.4?M,while that of HOTZ-3 was as low as 96.5 n M,which made it possible to monitor low concentrations of hydrogen peroxide in cells.Through confocal imaging of He La cells,HOTZ-1 successfully imaged exogenous hydrogen peroxide in cells,and HOTZ-3 successfully imaged both endogenous and exogenous in cells.What's more worth mentioning is that HOTZ-1 and HOTZ-3 were able of imaging exogenous hydrogen peroxide in nematode.It provides the possibility to further study the relationship between the content of hydrogen peroxide in objects and various diseases.Based on the thione moiety that can specifically recognize hypochlorous acid,with rhodamine derivatives and the semi-flower cyan structure as the fluorophore,three certain structural characteristics NIR fluorescent probes HCTZ-1,HCTZ-2 and HCTZ-3 for the detection of hypochlorous acid have been synthesized in this paper.Spectroscopic measurements evaluated with the condition of Et OH:PBS=2:8(p H=7.4)indicated that after HCTZ-1 reacted with Na Cl O/HCl O,the fluorescence maximum emission was red-shifted from 680 nm to 725 nm,and the change was very significant.In the detection limit experiment,the detection limit of HCTZ-1 was calculated to be as low as 21.8 n M.By confocal imaging of He La cells,HCTZ-1 successfully imaged exogenous hypochlorous acid in cells.Nematode experiments show that HCTZ-1 can successfully image exogenous hypochlorous acid in nematodes.Based on the halogens can be replaced by biological thiols,the semi-floral structure was used as the fluorophore,a fluorescent probe GSHTZ-1 for the detection of biological thiols NIR has been synthesized in this paper.Spectroscopic measurements evaluated with the condition of DMSO:PBS=2:8(p H=7.4)indicated that after GSHTZ-1 reacted with GSH/Cys/Hcy,the fluorescence maximum emission was red-shifted from 680 nm to735 nm,and the change was very significant.In the detection limit experiment,the detection limits of GSHTZ-1 for GSH,Cys,and Hcy were 92.4 n M,36.5 n M,and 62.0n M,respectively.By confocal imaging of He La cells,GSHTZ-1 successfully imaged both endogenous and exogenous GSH in cells.In the nematode imaging experiment,GSHTZ-1 can successfully image exogenous GSH in nematodes.To sum up,this paper synthesizes three series,a total of seven fluorescent probes for the detection of small biological molecules by using different structures of fluorophores and specific recognition groups.Experiments have proved that these probes have successfully achieved the detection of target molecules and optical imaging,which provides new optical research methods for the research of these small biological molecules in biology and medicine,and further promotes the development of fluorescent probes.