Synthesis And Bio-application Of Pyrene-based Fluorescent Probes

Fluorescent probes technique,as a rapid,sensitive and non-invasive method,have been widely used in the fields of analytical detection.Among lots of fluorophore,pyrene is often used to construct fluorescent probes due to its high fluorescence quantum yield,high absorption coefficient and good stability.In this paper,three fluorescent probes with pyrene as fluorophore were synthesized and used for the detection of CN^-,ClO^- and HSO₃^-,respectively.The main contents are as follows:Chapter 1: This chapter mainly introduces the application of molecular recognition and the common analytes in our organisms or daily life,and introduces the concept and recognition mechanisms of fluorescent probes briefly.In addition,the research progress of fluorescent probes based on pyrene was introduced in detail.Chapter 2: We design and synthesize a novel fluorescent probe 1-（pyrene-1-yl）-3-（N-ethylcarbazole-3-yl）-acrylketone（probe 1）.The probe 1 has a emission peak at 545 nm,and its fluorescence intensity increased and blue-shifted to 488 nm with the addition of CN^-.It can selectively detect CN^- in various anions and its sensitivity is high.Linear fitting results show that the linear range is 0-20 μM and the detection limit is 0.79 μM.The most noteworthy is that probe 1 has been successfully applied to the detection of CN^- in cells.Chapter 3: In this chapter,a turn-on fluorescent probe 1-（pyrene-1-yl）-3-（4-bromothiophene-2-yl）-acrylketone（probe 2）for the detection of ClO^- was synthesized by linking 1-acetylpyrene with 4-bromothiophene-2-formaldehyde.Probe 2 has the advantages of good selectivity,high sensitivity and wide linear range（0-80 μM）,and the detection limit is 4.63 μM.In addition,the results of probe 2 in Hep G-2 cell imaging are the same as the trend of fluorescence change,which indicates that the probe can be used to detect intracellular ClO^- in Hep G-2 cells.Chapter 4: Probe 3 was synthesized by the reaction of 1-acetylpyrene with 4,5-dibromothiophene-2-formaldehyde instead of 4-bromothiophene-2-formaldehyde in chapter 3.Probe 3 can be used to detect HSO₃^- in water/DMSO（9/1,v/v）.When HSO₃^- was added into the probe solution,the fluorescence intensity of probe 3 at 530 nm decreased gradually,while the fluorescence intensity at 420 nm increased continuously.The reaction can be completed in 2 min with high sensitivity.The linear range is 0-35 μM and the detection limit is 0.77 μM.Selective and anti-interference experiments show that probe 3 can detect HSO₃^- in complex environment.It was found that the reaction mechanism between probe 3 and HSO₃^- is Michael addition by ¹HNMR and mass spectrometry.The ICT process between electron donor（pyrene） and electron acceptor（4,5-dibromothiophene） is blocked because of the addition of HSO₃^-.In addition,the probe has been successfully applied to detect HSO₃^- in cells,zebrafish and nematodes.This study provides a method for rapid detection of HSO₃^- in vivo,and provides a basis for future research.