Study On Zinc Ion Fluorescence Sensor And Ph Colorimetric Sensor Based On Triphenylamine Derivatives

Abstract:Zinc,as the microelement in the organisms,plays a significant part in maintaining the life activities of organisms,such as gene expression,neuronal signal transmission.But if the amount of zinc ions in the human body deviates from the normal value,it would lead to diabetes,prostate cancer and other diseases.In recent years,most of the zinc was discharged into the environment in the form of Zn²⁺ions due to the increase of human activities and the excessive exploitation and using,this behavior has caused serious environmental pollution and affecting the normal life of human beings.p H value as one of the important chemical indicators of food shelf life,its changes can reflect whether food can be eaten by humans,and it is also an important indicator for industrial wastewater testing.The real-time detection for it has attracted people’s attention,especially the p H is in the neutral range which is very easy to change.Therefore,high selectivity and sensitivity are necessary for the detection of zinc ions in industrial products,environments and organisms,as well as the detection of the neutral p H range in the environment.In view of the unique molecular structure and optical properties of triphenylamine group,in Chapter 2,we designed and synthesized a new fluorescence sensor TPA-PN based on Schiff base of triphenylamine.When the Zn²⁺ion is 0 to 20μM in DMF-H₂O（V:V=1:1）,the detection of Zn²⁺ion by TPA-PN has good linearity,the high sensitivity detection of Zn²⁺was realized,detection limit was 19.134 n M and the binding constant was 3.24×10⁴ M^-1.After adding Zn²⁺ions,the TPA-PN solution showed obvious fluorescence enhancement phenomenon at 560 nm,and the Stokes shift was 110 nm,which is larger than the generally reported fluorescence sensor.In the detection system,TPA-PN showed excellent selectivity and anti-interference ability,and the common interference ions had little effect on the sensing of TPA-PN.And the reversible detection of Zn²⁺was realized by Na₂EDTA.The species of TPA-PN and zinc were clarified at different p H.Besides,the interaction properties and fluorescence mechanism were demonstrated by the density functional theory（DFT）calculation,¹H NMR titration,FT-IR and MS.What’s more,it provided a new real-time detection method and the potential for in vivo detection..In Chapter 3,a pH-sensitive colorimetric sensor TPA-BTAP was synthesized through the connection of triphenylamine and azo dye.It could achieve rapid and sensitive detection of p H in CH₃CH₂OH-H₂O（V:V=3:7）solution.The state of TPA-BTAP under different p H conditions was studied by potentiometric titration experiments and DFT calculations and the sequence of TPA-BTAP binding protons under different p H conditions was also calculated.Real-time detection can be achieved by preparing the form of test paper.Finally,the principle of color change of TPA-BTAP under different p H is explained.