乳制品中大肠杆菌的高灵敏度和强抗干扰性电化学检测方法研究

项目名称： 乳制品中大肠杆菌的高灵敏度和强抗干扰性电化学检测方法研究

项目编号： No.21205051

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 分析化学

项目作者： 张新爱

作者单位： 江苏大学

项目金额： 25万元

中文摘要： 乳制品中大肠杆菌的灵敏、准确检测对提高乳制品质量并保障其消费安全具有重要的现实意义。本项目将纳米技术与电化学分析技术相结合，利用抗体和抗原之间的特异性相互作用，构建电化学免疫分析体系，实现对乳制品中大肠杆菌的高灵敏度和强抗干扰性检测。我们利用电沉积法、溶胶-凝胶法制备异质包裹层修饰的纳米材料，提高纳米复合材料的生物亲和性、导电性和催化活性，并将其作为电极表面修饰材料和生物分子固定基底构筑纳米-生物功能界面，达到检测过程中放大电化学信号、提高灵敏度的目的；鉴于乳制品成分十分复杂，我们利用高度专一性的抗大肠杆菌单克隆抗体作为捕获抗体，依据抗体对单一大肠杆菌抗原位点的特异性识别和结合功能建立免疫分析方法，有效消除乳制品中蛋白质、脂肪、金属离子等因素对大肠杆菌检测结果的干扰，为乳制品中大肠杆菌的检测提供新的思路和方法。

中文关键词： 乳制品；大肠杆菌；高灵敏度；强抗干扰性；电化学检测

英文摘要： The sensitive and accurate analysis of Escherichia coli (E. coli) in dairy products is of great practical significance to improve the quality of dairy products and to ensure the consumer safety. Combining nanotechnology with electrochemical sensing technology, electrochemical immunoassay was developed for E. coli detection in dairy products with high sensitivity and strong anti-interference capability by using the specific recognition between antibodies and antigen. In this project, the nanomaterials were modified with the heterogeneous layer to design nanocomposites with high biocompatibility, conductivity and catalytic activity by electrodeposition and sol-gel method. The prepared nanocomposites served as the modified materials on electrode surface and fixed substrate of biological molecules to construct nano-biological function interface for electrochemical signal amplification and sensitivity improvement. In view of the complexity of the dairy ingredients, we used anti-E. coli monoclonal antibody as capture antibody (cAb). On basis of the specific recognition between antibodies and antigen, the immunoassay strategy was proposed to effectively eliminate the interference of the other ingredients in dairy products, which provided a promising strategy for the analysis of E. coli in dairy products.

英文关键词： dairy products；Escherichia coli；high sensitivity；strong anti-interference capability；electrochemical assay