Synthesis Of Small Molecule Fluorescence Probe And Applications In Bioanalysis

Herein,new fluorescent perylenebisimide based derivatives were synthesized and utilized as probe for cellular imaging in biological systems.The first chapter discusses the luminescence principle of the fluorescent probe and their modes of response in detail.Further,it summarizes the relevant research conducted in recent years and clarifies the reasons for choosing the subject.In the second chapter we reported the synthesis of a fluorescent probe M-PBI containing a morpholine group substituted with a chlorine atom at the bay position and used it for lysosomal imaging.The probe is employed to study the effect of pH disturbances in lysosomes on cells.The probe is simple to synthesize,it has a sensitive response to pH,and has a good linear relationship between pH 3 to 5.86.The calculated pKa is found to be 4.73,which is consistent with the pH microenvironment in lysosomes,and can be used for cell lysosomal imaging.In addition,the probe has excellent photostability(i.e.no fluorescence quenching has been observed within 3h),high selectivity,reversibility and anti-interference ability,which can greatly reduce intracellular interference.At the same time,the probe M-PBI only has the characteristics of water solubility under acidic conditions.Hence the probe can be used as a no-clean dye for in vivo imaging.The probe M-PBI is successfully employed in 4T1 cells to detect the pH of intracellular lysosomes.The gaseous signals of molecule NO occupy an important position in the cell,and the disturbances in the concentrations of NO will have an impact on physiological functions.In order to be able to monitor the intracellular [NO],we synthesized a hydrazine-modified perylenebisimide(PBI)derivative(Probe N-PBI)as reported in Chapter III.Due to the introduction of the hydrazine functional group,N-PBI forms a D-π-A structure,resulting in a larger spectral red shift compared to traditional PBI derivatives.The probe displayed large Stokes-shift and strong pH stability,which can minimize the interferences to fluorescence sensitivity caused by self-absorption.In addition,we used the probe N-PBI for the detection of NO in vitro.The spectroscopic study revealed N-PBI can specifically react with NO to form a new cyclic conjugated product to induce the blue shift in the spectrum.The response of PBI and NO has a good linear relationship,and the detection limit is calculated to be as low as 13 nM.We used it for 4T1 cell imaging experiments.The results show that N-PBI has low toxicity,rapid response,strong anti-interference ability,and can sensitively detect exogenous and endogenous NO.The probe has near-infrared emission,which also lays a solid foundation for in vivo experiments.