Study On Fluorescent Probe Of Fluorescein-based Cu(?)

Copper ion is a trace element required by the human body and is involved in the synthesis and transcription of lots of enzymes.Therefore,the content of copper ions in the human body is one of important factors which affect their health.However,the imbalance of copper(I)content in the body which cause a series of diseases,such as Menkes syndrome,Wilson disease,amyotrophic lateral sclerosis and Alzheimer's disease and so on.So the detection of copper(I)ions in human body has the important practical significance.Recently,the application of vivo labeling of fluorescent probes in cell biology is a novel research field,and it also provides an effective method for the detection of copper(I)in vivo.The small molecule probes based-on fluorescent play an extremely important role in chemical probes due to their basic advantage and "on-off" state of fluorescence.Based on the reasons mentioned above,a series of novel fluorescein-reactive copper(I)probes were designed and synthesized hoping to find an effective synthetic route for the fluorescein probe and prepared various fluorescein-reactive copper(I)probes with shorter reaction time,longer excitation wavelength and fluorescence emission wavelength,lower detection limits and higher quantum yields.The thesis mainly includes the synthesis of probes molecules and the basic performance tests of them.The main steps of the synthesis include: 1)cyclization of 2,2',4,4'-tetrahydroxybenzophenone to give a fluorescent ketone,and protection of two OH goups of fluoroketone by using TBSCl(tert-butyldimethylsilyl chloride);2)the TBS-protected fluorescent ketone reacts with the corresponding Grignard reagent,and then deprotection of TBS to prepare various 9-position aromatic-substituted fluorescein cores;3)the target probes were obtained from fluorescein by undergoing O-methylation,reduction and nucleophilic reaction with TPACl.Then the pH effect,reaction time,concentration and ion selectivity were tested,then the binding constants of ion and detection limits were calculated.Compared to the previous one-step condensation method,the designed synthetic route in this thesis can prepare different 9-substituted fluorescein cores by varying the Grignard reagent.This route can quickly prepare various fluorescences.The test results also show that such reactive probes have the advantages of good specificity,high sensitivity,large binding constant and low detection limit.In addition,the reaction time is generally 60-120 min,the fluorescence intensity is high,and the emission wavelength is in the visible light region whicn is close to red light.