BAS-SPR多级增强对典型BMZs杀菌剂的高效识别机理

Benzimidazole (BMZs) fungicides with the characteristics of high efficiency, low toxicity, and broad-spectrum, becomes a key food residue monitoring object. Since the teratogenic and mutagenic effects were found in laboratory animals and target animals,the more stringent limits will also be promulgated. SPR technology was especially fitting for the large numbers of sample analysis due to the advantage of simple pre-treatment process and less human disturbance with high degree of automation. However, the bottlenecks of weak response signal and low accuracy on small molecules, as well as over-reliance on antibody quality, has impeded the application in ultra-sensitive detection for the surface plasmon resonance sensor (SPR) technology. How to improve the SPR signal identification of small molecule target to enhance the efficiency and accuracy of detection is taking an important role in food safety testing. The study is designed using the sensitive membrane of the sensor chip surface in situ synthesis of biotin-avidin system (BAS) as a recognition element with the identification signal of small molecule to improve the SPR signal identification of small molecules thus to develop the BAS signal amplification SPR sensor. In addition, the Langmuir kinetic adsorption model, with the reactants map information between the reactants was adopted in this project, which further reveals the high efficient identification of the BAS sensitive film, thus also provide certain theoretical support mechanism to the application of the signal amplification strategy to SPR sensor technology from the molecular level.

苯并咪唑类(BMZs)杀菌剂具有高效、低毒、广谱的特点。由于在实验动物和靶动物中显示的致畸和致突变作用，BMZs成为了食品残留中重要的监控对象，更加严格的限量标准也将相继颁布。SPR技术因样品前处理简单，人为干扰因素少，自动化程度高等优点，特别适合大量样品的食品检测。然而SPR对小分子识别信号不高、检测灵敏度和准确度相对较低，以及过分依赖抗体质量，阻碍了其在超灵敏检测中的应用。因此，如何提高SPR对小分子的识别信号，从而提高检测的效率及准确性，对其在食品安全检测中的应用具有重要的意义。本项目在传感器芯片表面原位合成BAS信号放大敏感膜作为识别元件，以提高SPR对小分子的识别信号，从而构建BAS信号放大SPR传感器。另外，本项目采用Langmuir动力学吸附模型，结合反应物之间的图谱信息，从分子层面进一步揭示BAS敏感膜的高效识别机理，为信号放大策略在SPR传感器中的运用提供一定的理论支持。

本研究针对我国食品产业长期遭遇的技术壁垒和突发食品安全问题，从当前传感器领域研究热点出发，针对SPR对小分子有害物的检测方法中相应信号偏低，准确度不高和在多种物质检测中分子识别能力不高的两大技术缺陷问题，基于生物素-亲和素的高度特异性结合力、桥联作用以及放大作用，将生物素-亲和素系统用于表面等离子共振传感器。通过对再生液（盐酸、磷酸、甘氨酸等）、反应缓冲液（PBS、PBST、HBS）、反应时间、流速等系统条件进行优化，与抗体结合的静态平衡吸附实验分析，研究BAS膜与农药的结合特性，得到最佳的反应体系和反应程序，绘制针对苯并咪唑杀菌剂的标准吸附曲线，明确检测灵敏度、检测限及通用性。研究果蔬等样品的前处理方法，力求省时、简单、高效；采用动力学模拟对反应动力学速率常数、亲和力常数等参数进行计算，结合试验结果，对苯并咪唑杀菌剂在芯片表面与识别元件的相互作用进行理论计算,在分子层面探索BAS-SPR信号多级增强的作用机理。