Henan Province Engineering Research Center for Food Safety Control of Processing and Circulation, College of Food Science and Technology, Henan Agricultural University, 63 Nongye Road, Zhengzhou, 450002, Henan, China.
The Third Affiliated Hospital of Henan University of Traditional Chinese Medicine, Zhengzhou, China.
Mikrochim Acta. 2021 Jan 28;188(2):59. doi: 10.1007/s00604-021-04715-2.
A homogeneous fluorescence quenching immunoassay is described for simultaneous separation and detection of aflatoxin M (AFM) in milk. The novel assay relies on monoclonal antibody (mAb) functionalized FeO decorated reduced-graphene oxide (rGO-FeO-mAb) as both capture probe and energy acceptor, combined with tetramethylrhodamine cadaverine-labeled aflatoxin B (AFB-TRCA) as the energy donor. In the assay, AFB-TRCA binds to rGO-FeO-mAb in the absence of AFM, quenching the fluorescence of TRCA by resonance energy transfer. Significantly, the immunoassay integrates sample preparation and detection into a single step, by using magnetic graphene composites to avoid washing and centrifugation steps, and the assay can be completed within 10 min. Under optimized conditions, the visual and quantitative detection limits of the assay for AFM were 50 and 3.8 ng L, respectively, which were significantly lower than those obtained by fluorescence polarization immunoassay using the same immunoreagents. Owing to its operation and highly sensitivity, the proposed assay provides a powerful tool for the detection of AFM.
本文描述了一种用于牛奶中黄曲霉毒素 M（AFM）的同时分离和检测的均相荧光猝灭免疫分析方法。该新方法依赖于功能化 FeO 修饰的还原氧化石墨烯（rGO-FeO-mAb）作为捕获探针和能量受体，结合四甲基罗丹明 cadaverine 标记的黄曲霉毒素 B（AFB-TRCA）作为能量供体。在该测定中，在不存在 AFM 的情况下，AFB-TRCA 与 rGO-FeO-mAb 结合，通过共振能量转移猝灭 TRCA 的荧光。重要的是，免疫测定法通过使用磁性石墨烯复合材料将样品制备和检测集成到单个步骤中，避免了洗涤和离心步骤，并且该测定法可以在 10 分钟内完成。在优化条件下，该测定法对 AFM 的目视和定量检测限分别为 50 和 3.8ngL，明显低于使用相同免疫试剂的荧光偏振免疫测定法获得的检测限。由于其操作简单和高灵敏度，该方法为 AFM 的检测提供了有力的工具。
