Design, Synthesis And Properties Of Disubstituted Polyacetylene Fluorescent Probes

Application of chemical sensors for many areas and disciplines with a huge,high sensitivity and ease of operation are two of main problems of the sensor,fluorescence can easily meet those requirements,based on fluorescent sensors for chemical sensing is one of the most promising candidates.The development of fluorescent materials attracted the attention of scientists,because it is implemented as a true sensory systems are the most intuitive.Conjugated polymers have become one of the most important class of conductive material,because they are easier to chemical signals into optical signal,and because of the effect of molecular wires make signal amplification,cause the interest of many researchers.In this paper,two disubstituted polyacetylene fluorescent probes were designed and synthesized,and their structures were characterized by 1H NMR,13C NMR,MS,and IR spectra.Then,we further studied the optical properties and the detection ability of the designed and synthesized compounds,and made some practical water samples detection experiments,and made the test paper as the testing platform,certain results have been achieved.This thesis is divided into three parts.Firstly,the design and working principle of the fluorescent sensor are introduced briefly,and then the conjugated polymer fluorescent probe is introduced.The second part is the design and synthesis of a series of disubstituted polyacetylene fluorescent probes P1-P4.By investigating the literature we can know that,Pd²⁺ can coordinate with N,S atoms,and we adjust the specificity of Pd²⁺fluorescence sensors by changing the type and number of N,S atoms in polyacetylene pendant groups.Comparable experiments show that compound P3 has better selectivity and sensitivity for detection of Pd²⁺.As we all know,most pesticides contain N,P,S and other elements,so we envisage a kind of pesticide molecules from the P3/Pd²⁺complex will be won on the Pd²⁺,so as to achieve the effect of detection of pesticide molecules.The experimental results showed that P3/Pd²⁺ complexes could specifically detect thiophanate-methyl and the detection limit was 12.1 nM.Then we try to do some practical application of the sensor,in the actual water sample detection sensor P3 can be a good test of Pd²⁺,and then we make P3 with a test paper load can also achieve the detection of Pd²⁺.The third part is the design and synthesis of another disubstituted polyacetylene fluorescent sensor P5.After nitrogen-triazole is attached to the branched-polyacetylene branch,the nitrogen atom can coordinate with Cu²⁺.By the energy transfer,when the Cu²⁺ ion is added,the fluorescence of P5 will be turn off,this change was then recorded using a fluorometer to measure the effect of Cu²⁺.Glyphosate is a pesticide which containing N,P and other elements,is currently widely used.Glyphosate can form complexes with Cu²⁺ in the form of 1:1,so we try to use P5/Cu²⁺ complex to detect glyphosate molecules.The results showed that the complex of P5/Cu²⁺ could be used to detect glyphosate,and the selectivity was good and the sensitivity was high.