Design,Synthesis Of Fluorescent Probe Derived From Quinoline,Carbazole And Its Application In Food Inspection

Metal ion is one of the important testing items in the food,there are atomic absorption spectroscopy?AAS?,spectrophotometry?UV-VIS?,inductively coupled plasma mass spectrometry?ICP-MS?and other detection methods nowadays,but they have some common shortcomings in terms of instrument operation and detection time,while Fluorescent probe assay possesses high sensitivity,strong specific identification,short detection time,simple operation and other advantages.In this paper,quinoline and carbazole fluorophore as matrix,three kinds of fluorescent molecular probes?FP1,FP2,FP3?were designed and synthesized through the coupled reaction between connecting arm and DPA?N,N-Di-2-picolylamine?,and they would be used to detection of metal ions in the preserved egg after testing of fluorescent properties.The main results were as follows:1?Carbazole fluorophore as matrix,two kinds of fluorescent molecular probe,FP1and FP2 were designed and synthesized.FP1 had specific recognition function for Co²⁺,we found that other metal ions had no effect of FP1on the fluorescence quenching response of Co²⁺by metal ion competitive recognition experiment.2?In HEPES testing system,other metal ions had no effect of FP2 on the specific recognition response of Zn²⁺and Cu²⁺.After complex reaction between FP2 and Zn²⁺,intensity of fluorescence quantum yield increased 3.2 times by Photoinduced electron transfer?PET?.When the same amount of Cu²⁺was added to above testing system,connective sites between FP2 and Zn²⁺was replaced by Cu²⁺,fluorophore of system was quenched instantaneously,and replacement process resulted in quenching of fluorophore in the system irreversibly.3?Quinolinefluorophore as matrix,a fluorescent molecular probe FP3was designed and synthesized.In HEPES neutral or slightly alkaline testing conditions,fluorescence intensity of FPI reached the maximum value,and its fluorescence quantum yield was 0.091at this moment.Results of metal ion competition recognition experiment showed that Co²⁺had synergetic fluorescence quench effect on FP3,and other metal ions had no effect of FP3on the response effectiveness of Cu²⁺.4?Based specific recognition function of FP1,FP2 and FP3 on different mental ions,we established detection method of trace metal ions in preserved eggs.We found that the content of Co²⁺in preserved eggs was almost 0 after detecting by FP1.Cu²⁺and Zn²⁺existed in preserved eggs generally,fluorescence response of FP2 on metal ions would be disturbed;When Cu²⁺was between 0¹0?M in solution,response value of FP3on Cu²⁺was better,the linear regression equation was y=-10.28x+117.66,R² was 0.99,testing standard deviation was 0.16,the recovery was 99.3%,we applied this method to detection of Cu²⁺in preserved eggsand found the content of Cu²⁺was 9.68?g/g,and the result was not much different from the result from atomic absorption spectrophotometry?0.49ug/g?,Therefore,FP3 was suitable for quantitative fluorescence detection at Cu²⁺coexist system.