Design And Synthesis Of Dual-excitation Fluorescent Probe,Eu~Ⅲ-dtpa-bis(HBT),and Application In Detection Of Hydrazine

Hydrazine is widely used in many fields such as chemical industry,aerospace and medicine because of its alkalinity and reducing property.However,hydrazine is also a potential carcinogen,if improperly handled and discharged into the environment,which will cause serious environmental pollution and harm to human health.Therefore,it is important to find a simple,rapid and sensitive method to detect hydrazine in the environment.The traditional methods to detect hydrazine include spectrophotometry,chromatography and electrochemistry.Compared with these detection methods,fluorescence probe detection method has the advantages of short detection time,simple processing,good selectivity and high sensitivity.The fluorescence probe method mainly uses the interaction between the detection substance and the detected substance to change the fluorescence intensity or the fluorescence emission position to verify the existence of the detected substance.It can convert the complex physical,chemical or biological reactions inside a substance into visible fluorescence signals,which is convenient for people to study.Therefore,it has broad application prospects in environmental monitoring,industrial production,clinical medicine and scientific research.In this paper,a novel dual-excitation fluorescent probe EuⅢ-dtpa-bis(HBT)was designed and synthesized to accurately detect trace amounts of hydrazine in water.The influence factors of EuⅢ-dtpa-bis(HBT)as a dual-excitation fluorescent probe for detecting hydrazine,such as solution pH values,hydrazine concentration and presence of co-existing substances,were investigated under the excitation of 270 nm and 325 nm wavelength lights,respectively.The corresponding detection mechanism is proposed.Finally,the applicability of EuⅢ-dtpa-bis(HBT)for detecting hydrazine in actual water samples and living cells was tested.The specific research contents are as follows:First,the effect of solution pH values on the detection of hydrazine by using EuⅢ-dtpa-bis(HBT)as a fluorescent probe was investigated.The changes in fluorescence intensity of EuⅢ-dtpa-bis(HBT)and EuⅢ-dtpa-bis(HBT)+N2H4 solutions were investigated with the change of solution pH values(2.00-11.00).Second,the effect of hydrazine concentration on the fluorescence spectra of EuⅢ-dtpa-bis(HBT)was studied.The fluorescence intensity of EuⅢ-dtpa-bis(HBT)solution was investigated with the change of hydrazine concentration(0.00×10-5 mol/L-10.00×10-5mol/L).Thirdly,the selectivity of EuⅢ-dtpa-bis(HBT)as a dual-excitation fluorescent probe for hydrazine and whether coexisting substances interfere with the detection of hydrazine were investigated.Other substances coexisting with hydrazine in environmental water such as K+,Na+,Zn2+,Mg2+,Ba2+,Ni2+,Mn2+,Ca2+,Cr3+,Al3+,Fe3+,Cl-,ClO-,SO42-,glucose,H2O2 and NH3 H2O are added to EuⅢ-dtpa-bis(HBT)and EuⅢ-dtpa-bis(HBT)+N2H4 solution,respectively.The changes in fluorescence intensity of EuⅢ-dtpa-bis(HBT)and EuⅢ-dtpa-bis(HBT)+N2H4 were observed.Fourth,the accuracy of detecting hydrazine in real water samples by using EuⅢ-dtpa-bis(HBT)as a dual-excitation fluorescent probe was studied.The change in fluorescence intensity of EuⅢ-dtpa-bis(HBT)was observed by varying the amount of hydrazine that added to EuⅢ-dtpa-bis(HBT)solution in different water samples.Fifth,the toxicity of EuⅢ-dtpa-bis(HBT)to BV2 cells was tested,and the difference in fluorescence of EuⅢ-dtpa-bis(HBT)before and after the addition of hydrazine to BV2 cells was compared.In addition,the applicability of EuⅢ-dtpa-bis(HBT)in detecting hydrazine in living cells was investigated.