Design And Synthesis Of Fluorescent Probes For Sulfur Dioxide Derivatives And Hypochlorous Acid Detection And Their Application To Bioimaging

Sulfur dioxide derivatives are widely used in our daily life as preservatives in food and beverage to prevent food oxidation and bacterial growth.The industrialization development facilitates the extensive combustion of coal,oil and fossil fuels,which led to a large amount of SO2 released into the air.Low doses of sulfite have less effect to healthy,however,above certain concentration level of sulfur dioxide derivatives could cause some damage,such as: respiratory diseases,cancer and so on.Hypochlorous acid is a kind of byproduct produced by the process of natural oxidative metabolism in living life,which is closely related to the physiological and pathological processes.However excessive production of hypochlorous could cause cancer,arthritis and other diseases.Therefore,it is significance to quantificationally detect sulfur dioxide derivatives and hypochlorite by using fluorescence sensing methods.In this paper,we designed and synthesized four probes for the detection of the sulfite(T1 and T2),bisulfite(T3)and hypochlorite(T4),and their photophysical properties and biological applications were studied.The results showed that these probes displaying excellent selectivity and good spectral signal response.These probes have been successfully applied in the bioimaging in living cells and caenorhabditis elegans.This paper includes the following three research contents:1.Fluorescent probe T1 and T2 based on coumarin fluorophores were used to detect sulfite.The probes T1 and T2 were investigated in CH3CN-HEPES(0.02 M,pH 7.4)(V/V = 2:8)buffer solution and CH3CN-PBS(0.02 M,pH 7.4)(V/V = 2:8)buffer solution separately.Probe T1 showed better selectivity to sulfite,and it was successfully applied in Hela cells imaging for sulfite detection.2.The probe T3 was easily obtained by the condensation of a hemicyanine dye with N-etyl-3,6-dicarboxy carbazole.In the study of photophysical properties,we observed obvious color change from yellow to colorless upon addition bisulfite to the probe T3 in DMF-PBS(0.01 M,pH 7.4)(V:V = 3:7)buffer,accompanied by a enhancement response of fluorescence.The probe T3 was successfully applied to the quantitative determination exogenous HSO3-in Hela cells and caenorhabditis elegans with fluorescence bioimaging method.3.The hypochlorite probe T4,an oxime,was synthesized from T3 using the reaction of aldehyde group of T3 with a hydroxylamine.As the addition of hypochlorite,the fluorescence was enhanced in the buffer solution of DMF-PBS(0.01 M,pH 7.4)(V/V = 4:6).In the presence of various interference ions,the probe T4 showed excellent selectivity.The probe T4 was successfully applied to the detection of exogenous generated ClO-in Hela cells and caenorhabditis elegans with fluorescence bioimaging method.