Fluorescent Probe For Detecting Hydrogen Sulfide And Zinc Ions Based On Naphthalimide Fluorophore

Hydrogen sulfide is widely present in living organisms and is an important active sulfur species in organisms.Many physiological processes in organisms have their involvement.For example,nerve conduction,blood pressure regulation,and insulin secretion play a vital role in maintaining the redox state in the body.Abnormal concentration of hydrogen sulfide in human body can cause many diseases,such as Alzheimer’s disease,liver cirrhosis,Parkinson’s disease and so on.At present,most of the reported hydrogen sulfide probes have some defects,such as cannot respond to hydrogen sulfide in a single way and the long reaction time.Therefore,it is urgent to develop a fluorescent probe with single response,good sensitivity and stability to hydrogen sulfide.Zinc ions play an important role in many biological processes.It is the second abundant transition metal ion found in physiology.It plays many roles in extracellular and intracellular functions.It is a necessary element for human body and is commonly found in nutritional supplements.The lack of zinc in the human body can cause many diseases such as Alzheimer’s disease,cerebral ischemia and epilepsy.But too much zinc can also affect your health.Therefore,it is very necessary to monitor the concentration of zinc ion in physiological level.In this paper,two fluorescent probes were designed based on naphthalimide fluorophores for the detection of hydrogen sulfide and zinc ions.1.A naphthalimide fluorophore was utilized to synthesize a fluorescent probe Z1for detecting hydrogen sulfide by linking 3,3-dithiodipropionic acid with the anticancer drug SN-38.When HS^-was added to the buffer solution of DMSO-PBS（0.01 M,pH=7.4）（V/V=1:1）,the Z1 solution changed from blue fluorescence to yellow-green fluorescence.The probe Z1 has excellent selectivity,high sensitivity and low detection limit for hydrogen sulfide.It has been successfully applied to the fluorescence imaging of Hela cells and can be used to detect the content of exogenous hydrogen sulfide in cells.2.Using naphthalimide and coumarin as fluorophores,DPA was used as a recognition group to synthesize a fluorescent probe T1 for detecting zinc ions.After the probe T1 is added with Zn²⁺in DMSO-PBS（0.01 M,pH 7.4）（V/V=3:7）buffer solution,the probe T1 solution changes from weak blue fluorescence to yellow-green fluorescence,and the high binding selectivity of the probe T1 solution to Zn²⁺could be achieved.