用于食品中β-内酰胺类抗生素残留分析的离子液体双水相浮选体系的建立及机理研究

β-lactam antibiotics is one of the major antibiotic residues in food. Residual antibiotics in food constitute a risk to human health, especially because they can contribute to the transmission of antibiotic-resistant pathogenic bacteria through the food chain. Therefore, to ensure food safety, analytical methods for the determination of β-lactam antibiotics in food are very important. The difficulty and emphasis of analytical methods lies in the separation and enrichment of residues..The aim of this project is to develop a fast and reliable separation and enrichment method for the determation of β-lactam antibiotic residues in food samples. The method is based on ionic liquid aqueous two-phase system(ILATPS) combined with gas solvent sublation,called ionic liquid aqueous two-phase system(ILATPFS).It will be studied to discuss the mechanism of phase separation for ILATPS,which including phase equilibrium of the ILATPS and factors on the formation of ILATPS such as types of ILs and salts,concentration of ILs and salts, pH value and temperature. In addition,The separation mechanism of β-lactam antibiotics in ILATPS will be discussed..The phase behaviors of the ILATPFS and effect of various parameters,such as the gas flow rate,pH,sublation time,temperature,types of ILs and salts, as well as concentration of ionic liquid and salt,on the sublation efficiency will be investigated in details and the optimal conditions of sublation will be obtained to develop a novel separation method based on ionic liquid aqueous two-phase flotation system for the separation and enrichment of β-lactam antibiotics in food. As a viable pretreatment technique for the determination of β-lactam antibiotic residues in food samples,the method will be highly efficient,fast,non-toxic and simple for the separation and enrichment of β-lactam antibiotics..Another key focus of this research is to discuss separation behavior and separation mechanism of β-lactam antibiotics in ILATPFS by FT-IR spectroscopy and UV-vis spectroscopy,together with calculating the kinetic and thermodynamic parameters.

β-内酰胺类抗生素是动物源食品中抗生素残留的主要来源之一，会对人体健康产生危害，也会导致耐药性微生物的传播。为保证食品安全必须对残留抗生素进行检测。抗生素残留检测的重点和难点是残留物的分离富集。为建立一种新的适用于食品中β-内酰胺类抗生素残留检测的前处理方法，本项目以离子液体和无机盐水溶液形成的双水相体系浮选β-内酰胺类抗生素为研究对象，考察影响离子液体双水相形成的因素以及β-内酰胺类抗生素在体系中的浮选行为。特别考察离子液体的组成对分相能力的影响以及分相无机盐的种类、盐的浓度、试液pH、表面活性剂、干扰成分、浮选时间和氮气流速等因素对双水相浮选效果的影响，确定影响浮选效率和选择性的主要因素。利用该体系分离/富集食品样品中β-内酰胺类抗生素残留，并对其分离机理进行初步研究，初步阐释离子液体双水相浮选体系对β-内酰胺类抗生素的浮选机理，为进一步研究抗生素分离富集方法提供科学依据和参考。

β-内酰胺类抗生素是动物源食品中抗生素残留的主要来源之一，会对人体健康产生危害，也会导致耐药性微生物的传播。为保证食品安全必须对残留抗生素进行检测。.抗生素残留检测的重点和难点是残留物的分离富集。为建立一种新的适用于食品中β-内酰胺类抗生素残留检测的前处理方法，本项目以离子液体和无机盐水溶液形成的双水相体系浮选β-内酰胺类抗生素为研究对象，以青霉素为目标代表物，考察影响离子液体双水相形成的因素以及β-内酰胺类抗生素在体系中的浮选行为。特别考察离子液体的组成对分相能力的影响以及分相无机盐的种类、盐的浓度、试液pH、表面活性剂、干扰成分、浮选时间和氮气流速等因素对双水相浮选效果的影响，确定影响浮选效率和选择性的主要因素。利用该体系分离/富集食品样品中β-内酰胺类抗生素残留，并对其分离机理进行初步研究，初步阐释离子液体双水相浮选体系对β-内酰胺类抗生素的浮选机理，为进一步研究抗生素分离富集方法提供科学依据和参考。