Synthesis And Biological Imaging Of Three Fluorescent Probes Based On Rhodamine

The fluorescent probe method has attracted the attention of many researchers due to its advantages of high sensitivity,good selectivity,non-invasiveness,and visualization.Fluorophore is one of the important components of fluorescent probes.As a common fluorophore,rhodamine is often used to construct fluorescent probes because of its good photobleaching resistance and high fluorescence quantum efficiency.In this thesis,the main research content is to use rhodamine as the parent fluorophore,introduce specific recognition groups,modify the specific sites to optimize probe performance,and construct several fluorescent probes for detecting disease-related substances.The specific content is as follows:(1)Design a fluorescent probe Rho-NO which can quantitatively detect nitric oxide(NO)with high selectivity.Before the addition of NO,the rhodamine spiro ring turned off and appeared to be non-fluorescent.After the addition of NO,the amino group in the probe selectively undergo N-nitrosation reaction with NO,which led to the opening of rhodamine spiro ring and the recovery of fluorescence.The quantitative detection of NO can be realized according to the change of fluorescence intensity before and after the reaction.The fluorescence intensity of probe solution had a linear relationship with NO concentration,the linear range was 0-100 ?M,and the detection limit was 0.0635 ?M.The probe can detect NO with high selectivity,and it can be successfully applied to the detection of NO in human serum and living cells based on its good biocompatibility,achieved good results in the imaging study of NO in zebrafish inflammation model.(2)Construct a fluorescent probe Rho-GSH that can quickly detect glutathione(GSH)with high selectivity.Before the addition of GSH,the rhodamine spiro ring turned off and appeared to be non-fluorescent.After the addition of GSH,the nitrobenzene part of probe selectively reacted with GSH,causing rhodamine fluorescence recovered and realizing the fluorescence “turn-on”.The probe can quickly respond to GSH(< 3 s),and solution fluorescent intensity had a good linear relationship with GSH concentration.The linear range was 0-5 m M,and the detection limit was 0.0496 m M.The probe achieved highly selective detection of GSH in the presence of other amino acids(including Cys and Hcy),and based on the good biocompatibility of probe,it had been successfully used for imaging GSH in living cells.(3)Synthesize a fluorescent probe Rho-Pt that can detect cisplatin with high selectivity.Before the addition of cisplatin,the rhodamine spiro ring turned off and appeared to be non-fluorescent.After the addition of cisplatin,the recognition group dithiocarbamate of probe selectively combined with cisplatin,the rhodamine spiro ring opend and emitted strong fluorescence.The detection of cisplatin by Rho-Pt was based on fluorescence recovery of probe solution before and after adding cisplatin.The complex ratio of Rho-Pt to cisplatin was 1:1,the fluorescence intensity of Rho-Pt solution had a good linear relationship with cisplatin concentration,the linear range was 16-50 ?M,and the detection limit was0.2677 ?M.Importantly,this probe had not only been successfully used to explore the reduction of cisplatin prodrugs in solution,but also successfully used to detect cisplatin in living cells.