基于稀土金属-多酚网络改性磁探针的食品中喹诺酮类抗菌药残留高灵敏免疫层析研究

动物源食品中喹诺酮类抗菌药残留是消费者健康的重要威胁。基于金纳米粒子的常规免疫层析法易受到动物源食品复杂基质的影响，其检测灵敏度低、稳定性差，难以满足痕量检测的需求。研究表明，Fe3O4磁纳米粒子可对食品基质进行净化并富集待测物，但是其存在信号强度弱等不足，不适合直接用作信号探针。本项目（1）采用稀土金属-多酚网络对Fe3O4纳米粒子进行表面荧光化改性，制备磁性-荧光复合纳米探针。（2）研究稀土金属-多酚网络与抗体分子的相互作用，实现抗体分子在探针表面高效定向偶联来提升抗体与待测物的结合效率。（3）研究抗体修饰后的磁性-荧光复合纳米探针对多种动物源食品的基质净化性能，并构建免疫层析检测方法。基于兼有磁富集净化性能和强荧光信号的复合纳米探针可实现复杂样品基质中痕量喹诺酮残留高灵敏度、高稳定性检测。本项目将为动物源食品中兽药残留的现场、即时检测提供新的研究思路和技术手段。

Residue of quinolone antibacterials in animal-derived foods is an important threat to human health. Conventional immunochromatographic assays based on gold nanoparticles are easily affected by the complex matrix of animal-derived foods, leading to the low detection sensitivity and poor stability, which is difficult to meet the needs of trace detection. Studies have shown that Fe3O4 magnetic nanoparticles (MNPs) can reduce the food matrix and enrich the analytes. However, MNPs have weak signal strength and other shortcomings, which are not suitable for direct use as signal probes in immunochromatographic assays. In this project: (1) rare earth metal-polyphenol networks are used to modify the surface of Fe3O4 MNPs to synthesize magnetic-fluorescent composite nanoprobes. (2) The interaction between the rare-earth metal-polyphenol networks and antibodies will be investigated to achieve efficient and oriented coupling of antibodies on the surface of the composite nanoprobes, improving the binding efficiency of the antibodies to the analytes. (3) The performance of the antibody-modified composite nanoprobes on the matrix purification of different animal-derived foods (pork, chicken, fish, milk and pig liver) will be studied, followed by the construction of immunochromatographic assays. Applying the composite nanoprobes with both magnetic enrichment ability and strong fluorescence in immunochromatographic assays can achieve the highly stable and highly sensitive detection of trace quinolone residues in complex food samples. This project will provide new research ideas for the on-site and rapid detection of veterinary drug residues in animal-source foods, which has important theoretical significance and application prospects.