Study On The New Method Of Detecting D-penicillamine,Picric Acid,Auramine O By Fluorescence Probe

Environment,food and medicine are the key factors for the sustainable development of the world and the competition of comprehensive national strength.Therefore,the development of accurate and efficient tools to identify and trace important molecules at the molecular level is the most important research in science and technology.Due to its advantages of high sensitivity,high selectivity,no damage to the test sample,rapid real-time detection and so on,the fluorescent probe has increasingly become an indispensable molecular tool in the field of modern life science and disease diagnosis.This paper mainly designed and synthesized three kinds of fluorescent probes were detected D-penicillamine,picric acid,and Auramine O.The main researches are as follows:1.L-tryptophan-Hg²⁺-D-penicillamine fluorescence spectroscopy and its logic applicationsBased on the quenching and recovery of L-tryptophan fluorescence,a simple,efficient and reproducible fluorescence switch sensor for D-PA detection was designed.In BR buffer solution at pH 5.2,Hg²⁺effectively combines with the carboxyl group on L-tryptophan to quench its fluorescence.D-Penicillamine was added,due to the stronger binding force between Hg²⁺and D-penicillamine makes Hg²⁺detachment from L-tryptophan and fluorescence restored.This phenomenon was designed as IMPLICATION's logic gate and was first applied to the detection of D-penicillamine.Fluorescence recovery and D-penicillamine concentration between 0.44?mol L^-1 and 50.0?mol L^-1 showed a good linear relationship with the detection limit of 0.13?mol L^-1.The method was used for the determination of D-penicillamine in medicine with satisfactory results.2.Design,synthesis and application of picric acid fluorescent probes based on the effect of inner filterSodium citrate and ammonium bicarbonate were used as raw materials to obtain carbon dots by one-step hydrothermal synthesis.It was characterized by fluorescence,infrared and UV spectroscopy.The results show that the carbon dots have good stability and the excitation does not change with the emission.The quantum yield is as high as 63%.Picric acid can effectively quench the fluorescence of carbon dots due to the inner filter effect.Under optimal conditions,the linear range was 0.95-50.0?mol^-1.The detection limit was as low as 0.28?mol^-1.The method was successfully applied to the determination of picric acid in tap water and the recovery rate was 95%-104%.At the same time,the reaction mechanism,the optimal reaction conditions,the impact of coexisting substances were studied.3.Synthesis of carbon dots by microwave method and its application in Auramine O detectionIn this paper,folic acid as a nitrogen source,tartaric acid as a carbon source,one-step microwave synthesis of fluorescent carbon dots with a quantum yield of 54%.It was characterized by transmission electron microscopy?TEM?,UV-vis,fluorescence spectroscopy,Fourier transform infrared spectroscopy?FTIR?and Raman spectroscopy.The results show that the synthesized carbon dots are spherical,uniform in size,good in dispersion and emission wavelength independent of the excitation wavelength,and have the advantages of salt tolerance,oxidation resistance and photobleaching.Surprisingly,the surface is rich in a large number of amino,carboxyl,hydroxyl and other groups.Auramine O has a larger molar absorption coefficient,and the absorption wavelength and emission wavelength of carbon has a great overlap.Based on the effect of the inner filter,a highly selective and highly sensitive method for determination of Auramine O was established.The detection limit was as low as36.0 nmol L^-1,which was lower than the reported test methods.This method has been successfully applied to the detection of Auramine O in Yuanhu Zhitong Tablets.