功能纳米探针的电化学免疫传感及其对食源性致病菌检测研究

The development of nanotechnology has led to a wide range of applications of nanomaterials which contains unique chemical, physical and mechanical properties. In order to overcome the defects of the traditional methods for detection of E. coli and other foodborne pathogens, such as lack of sensitivity and complexity in operation, this project focusing on the demands for food safety and human health in the aspect of analysis and detection will design ultra-sensitive electrochemical immunosensors by combining the high surface area of nanosphere with the polymer for assembling quantum dots (QDs). For designing the new nanoprobes for recognition with high loading, this research will synthesize a variety of new nanospheres and realize the functionalization of them with QDs using self-assembly technique. This research will further explore the mechanism of interactions between the nanosphere, polymer and QDs, and interface interactions between the molecules. By combing the specific recognition of the functional nanoprobes and stripping voltammetric analysis, the novel electrochemical methods for immunoassay without using of enzyme will be developed to realize the ultra-sensitive, simple and rapid detection for foodborne pathogens. This research work integrating the advantages of self-assembly technique, the nanospheres functionalized with QDs, immunoassay and electrochemical detection will build new analytical methods and mechanism. We anticipate that this research work can provide a new platform for fast detection of foodborne pathogens and promote the development of interdisciplinary field and immunoassay.

纳米技术的发展已使具有独特化学、物理和机械性能的纳米材料得到广泛应用。本项目围绕人类健康与食品安全在分析检测方面的需求，针对大肠杆菌等食源性致病菌检测方法的灵敏度低和检测程序复杂等问题，利用新型纳米球的大比表面积，通过天然聚合物将量子点层层组装到纳米球表面，实现信号放大，构建超灵敏电化学免疫传感新方法。研究工作将设计合成多种新型纳米球，以天然聚合物为交联分子，并结合层层自组装技术，用量子点进行功能化，探讨纳米球、聚合物以及量子点之间的相互作用规律和界面分子间的相互作用机制，构筑高负载量的新型纳米识别探针，并利用溶出伏安分析技术，建立高效无酶的电化学免疫传感新原理与新方法，以实现简单、快速和高灵敏的食源性致病菌检测。本项工作集成层层自组装技术、量子点功能化纳米球、免疫分析和电化学检测的优点，将建立新的分析原理与方法，为食源性致病菌快速检测提供了新的平台, 并促进相关交叉学科与免疫分析领域的发

本项目围绕人类健康与食品安全在分析检测方面的需求，针对目前食源性致病菌检测方法的灵敏度低和检测程序复杂等问题，利用新型纳米材料大的比表面积功能化量子点等信号分子，合成功能化纳米探针，实现信号放大，从而成功构建高灵敏电化学免疫传感新方法。本研究工作首先合成了多种新型纳米材料，其中包括碳纳米球、聚苯乙烯-丙烯酸纳米球、金纳米棒、半导体量子点以及纳米复合材料等。接着分别利用量子点、金属离子以及生物酶等信号分子功能化上述合成的新颖碳纳米球、聚苯乙烯-丙烯酸纳米球或金纳米棒，并进一步通过交联等方法将能特异性识别致病菌表面抗原的抗体成功组装到上述信号分子功能化的纳米探针表面，从而成功构建了生物相容性好、比表面积大且具有分子识别功能和信号放大作用的多功能纳米探针。研究工作中还利用层层自组装等方法设计了多种致病菌抗体在电极表面的固定化方法，提高了免疫反应效率与电化学免疫传感器稳定性。本项工作创造性地结合功能化纳米材料与电化学免疫传感的优点，拓宽了功能纳米材料的应用领域，促进了免疫分析领域的发展，为食品中食源性致病菌快速、高灵敏检测提供了新的平台。