Detection Of Amino Acids In Drugs By Fluorescence Probe Method And Its Application

Amino acid is the most basic unit of protein composition,but also raw materials for biological synthesis of protein.Amino acids are a very important nutrient for living organisms and are closely related to many life activities.The qualitative and quantitative analysis of amino acids is of great significance in industrial production,clinical diagnosis,life sciences and other research.At present,the common amino acid detection methods are mainly high performance liquid chromatography,gas chromatography,ion exchange chromatography,chromatography mass spectrometry,capillary electrophoresis,electrochemical methods,chemical methods,including formaldehyde titration and Kjeldahl method,Photochemical analysis and amino acid analyzer and other methods.However,the above methods are prevalent in the complicated operation,long measurement time and high cost of analysis.In contrast,the fluorescence probe method has the advantages of simple operation,high sensitivity,low detection limit and wide response range.Therefore,the establishment of a low detection limit,high sensitivity of the fluorescent probe method for the determination of amino acids is of great significance.This paper is divided into the following three aspects:1.In this paper,we briefly introduce the classification and function of amino acids,briefly describe the common methods of amino acid analysis in recent years,and summarize the basic principles of fluorescence analysis.2.We have studied several fluorescent probes for quantitative detection of amino acids:?1?In the Clark-Lubs buffer solution?p H=8.8?,fluorescence intensity of morin hydrate,which is quenched by Cu²⁺ can be enhanced when adding a certain amount of lysine,Thereby,we establish a fluorescence spectrometry method for the detection of lysine.When the excitation slit width is 5nm and emission slit width is 5nm,we get the following results: the linear regression equation:F=98.75+49.93C?mg/L?,correlation coefficient: R=0.9997,linear range: 1.0⁵.0mg/L;the detection limit:0.0057mg/L.?2?Ni²⁺ can form a complex with calcein in the presence of S?rensen buffer solution and surfactant aqueous solution of pH = 10.8 to calm the fluorescence of calcein.After adding a certain amount of aspartic acid,Aspartic acid can increase the fluorescence of Ni²⁺-calcein after quenching,and the increase is proportional to the concentration of aspartic acid in a certain range.Therefore,we have established a fluorescence probe method for the detection of aspartic acid.When the width of the slit is 3nm and the width of the emission slit is 5nm,the linear regression equation is:F=88.47+8.497C?mg/L?,the correlation coefficient is R=0.9981,the linear range is 1⁴0mg/L,detection limit is 0.0050mg/L.?3?In the Clark-Lubs buffer solution at pH 9.6 and the surfactant surfactant SDS,when the slit width is 3nm and the emission slit width is 5nm,the cysteine can make the quenched Pb²⁺-salicylfluorone The linear regression equation was:F=52.03+173.2C?mg/L?,the correlation coefficient was 0.9986,the linear range was 0.5⁵.0mg/L,and the detection limit was 0.00086mg/L.3.In this paper,we study the relationship between the fluorescence intensity and the content of amino acids and metal ions,and explore the reaction mechanism and complexing ratio between the fluorescent probe and metal ions and amino acids,and make a preliminary study.