Shandong Provincial Key Laboratory of Molecular Engineering, School of Chemistry and Pharmaceutical Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China.
Analyst. 2020 Feb 17;145(4):1368-1375. doi: 10.1039/c9an02543j.
In this study, a sensitive label-free electrochemical immunosensor was designed based on nanoporous Fe3O4 and a biotin-streptavidin system to specifically detect zearalenone (ZEN). Herein, nanoporous Fe3O4 was employed to carry streptavidin to prepare the highly sensitive immunosensor. The application of nanoporous Fe3O4 and the biotin-streptavidin reaction provided large amounts of antibodies on each conjugate, thus amplifying the detected signal. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were conducted to characterize the modification with ZEN. Factors which might influence the properties of the immunosensor, including concentration of nanoporous Fe3O4, pH of the buffer, incubation time and temperature were studied. Under the best conditions, the immunosensor displayed a highly sensitive response toward ZEN, ranging in concentration from 10.0 pg mL-1 to 3.00 ng mL-1 and 3.00 ng mL-1 to 12.0 ng mL-1, with a low detection limit of 3.7 pg mL-1. The results for analysis of human urine samples were satisfactory. Furthermore, this proposed method may find promising applications in the detection of other mycotoxins.
在这项研究中，设计了一种基于纳米多孔 Fe3O4 和生物素-链霉亲和素系统的灵敏无标记电化学免疫传感器，用于特异性检测玉米赤霉烯酮（ZEN）。在此，纳米多孔 Fe3O4 被用于携带链霉亲和素来制备高灵敏度的免疫传感器。纳米多孔 Fe3O4 的应用和生物素-链霉亲和素反应为每个缀合物提供了大量的抗体，从而放大了检测信号。采用循环伏安法（CV）和电化学阻抗谱（EIS）对 ZEN 的修饰进行了表征。研究了可能影响免疫传感器性能的因素，包括纳米多孔 Fe3O4 的浓度、缓冲液的 pH 值、孵育时间和温度。在最佳条件下，该免疫传感器对 ZEN 表现出高度灵敏的响应，浓度范围为 10.0 pg mL-1 至 3.00 ng mL-1 和 3.00 ng mL-1 至 12.0 ng mL-1，检测限低至 3.7 pg mL-1。对人尿样的分析结果令人满意。此外，该方法可能在其他真菌毒素的检测中具有广阔的应用前景。
