Zhou Cuiyun, Pan Shixing, Liu Puyue, Feng Niu, Lu Peng, Wang Zhipan, Huang Chenxi, Wu Long, Chen Yiping
College of Food Science and Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China.
School of Food Science and Engineering, Key Laboratory of Tropical and Vegetables Quality and Safety for State Market Regulation, Hainan University. Haikou, 570228, China.
Talanta. 2023 Jun 1;258:124357. doi: 10.1016/j.talanta.2023.124357. Epub 2023 Feb 17.
Aflatoxin M (AFM) contamination poses a serious threat to human health globally. Hence, it is necessary to develop reliable and ultrasensitive methods for the determination of AFM residue in food products at low levels. In this study, a novel polystyrene microsphere-mediated optical sensing (PSM-OS) strategy was constructed to solve the problems of low sensitivity and susceptibility to interference from the matrix in AFM determination. Polystyrene (PS) microspheres have the advantages of low cost, high stability, and controllable particle size. They can be useful optical signal probes for qualitative and quantitative analyses attributed to the fact that they have strong ultraviolet-visible (UV-vis) characteristic absorption peaks. Briefly, magnetic nanoparticles were modified with the complex of bovine serum protein and AFM (MNP-BSA-AFM), and biotinylated antibodies of AFM (AFM-Ab-Bio). Meanwhile, PS microspheres were also functionalized with streptavidin (SA-PS). In the presence of AFM, a competitive immune reaction was triggered leading to the changes in AFM-Ab-Bio concentrations on the surface of MNP-BSA-AFM. The complex of MNP-BSA-AFM-Ab-Bio binds with SA-PS to form the immune complexes due to the special binding of biotin and streptavidin. The remaining SA-PS in the supernatant was determined by UV-Vis spectrophotometer after magnetic separation, which positively correlated with the concentration of AFM. This strategy allows for ultrasensitive determination of AFM with limits of detection as low as 3.2 pg/mL. It was also successfully validated for AFM determination in milk samples, and a high consistency was found with the chemiluminescence immunoassay. Overall, the proposed PSM-OS strategy can be used for the rapid, ultrasensitive, and convenient determination of AFM, as well as other biochemical analytes.
黄曲霉毒素M（AFM）污染对全球人类健康构成严重威胁。因此，有必要开发可靠且超灵敏的方法来测定食品中低水平的AFM残留。在本研究中，构建了一种新型的聚苯乙烯微球介导的光学传感（PSM-OS）策略，以解决AFM测定中灵敏度低和易受基质干扰的问题。聚苯乙烯（PS）微球具有成本低、稳定性高和粒径可控的优点。由于它们具有强烈的紫外可见（UV-vis）特征吸收峰，因此可作为有用的光学信号探针用于定性和定量分析。简而言之，用牛血清蛋白和AFM的复合物（MNP-BSA-AFM）以及AFM的生物素化抗体（AFM-Ab-Bio）对磁性纳米颗粒进行修饰。同时，用链霉亲和素（SA-PS）对PS微球进行功能化。在AFM存在的情况下，引发竞争性免疫反应，导致MNP-BSA-AFM表面的AFM-Ab-Bio浓度发生变化。由于生物素和链霉亲和素的特殊结合，MNP-BSA-AFM-Ab-Bio复合物与SA-PS结合形成免疫复合物。磁性分离后，用紫外可见分光光度计测定上清液中剩余的SA-PS，其与AFM浓度呈正相关。该策略能够超灵敏地测定AFM，检测限低至3.2 pg/mL。它也成功地用于牛奶样品中AFM的测定，并且与化学发光免疫分析具有高度一致性。总体而言，所提出的PSM-OS策略可用于快速、超灵敏且方便地测定AFM以及其他生化分析物。
