The Development Of New Fluorescent Reagents And Their Application In The Analysis Of Amino Compounds In Food

Amino acids,as an important living substance,widely exist in living organisms.Meanwhile,amino acids are indispensable nutrients in various foods,which affect the taste,aroma and color of these products and have very complex biological functions.However,the use of some food additives,preservatives,and food packaging materials has also led to the emergence of a variety of carcinogenic amino pollutants in food.Therefore,the development of high-sensitivity and selective analytical methods to monitor these substances is essential for the study of the relationship between food and human health.High performance liquid chromatography(HPLC)has been one of the most commonly used detection techniques in the field of food and health security analysis due to its high resolution,high sensitivity,strong universality and simple sample processing.However,due to the fact that most amino compounds have no luminescence properties,the development of highly sensitive label reagents has been a top priority.In addition,the complexity and diversity of amino compounds in food also put forward higher requirements for the selective detection of different amino compounds.The focus of this study is to design and synthesize novel fluorescent reagents for labeling amino compounds and to develop analytical methods with high selectivity and sensitivity for the detection of amino compounds in food.The specific contents are as follows:Chapter one: Brief introduction to the amino compounds in food,the common analysis techniques of amino compounds,the research status of derivatization reagent used to label amino groups,the significance of the topic and the main work of this paper.Chapter two: A novel fluorescent labeling reagent 4-(carbazole-9-yl)-benzyl chloroformate(CBBC-Cl)was designed and synthesized,the structure was also confirmed and the spectral properties were characterized.A precolumn derivatization-high performance liquid chromatography-mass spectrometry analysis method using CBBC-Cl as the labeling reagent was established for the quantitative analysis of 20 amino acids in four types of tea,and the trend of amino acid content in different production processes was discussed in-depth.Chapter three: A mixed solution of acetic acid and hydrobromic acid was used as a denitration reagent,CBBC-Cl was used as a derivatization reagent,and dispersion liquid-liquid microextraction and high-performance liquid chromatography-fluorescence detection were used to achieve rapid analysis of nitrosamines in various foods.Chapter four: The inexpensive commercial reagent 2-formylphenylboronic acid(FPBA)was used as a switch-type fluorescent reagent,combined with high-performance liquid chromatography-fluorescence detection,achieved accurate and rapid analysis of semicarbazide in a variety of foods.The effects of various amino acids on the analysis of actual samples were investigated in-depth,and the results showed that the method was selective and sensitive.