Oil Crops Research Institute, Chinese Academy of Agricultural Sciences , Wuhan 430062, China.
Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture , Wuhan 430062, China.
Anal Chem. 2017 Nov 7;89(21):11520-11528. doi: 10.1021/acs.analchem.7b02794. Epub 2017 Oct 11.
Aflatoxins and zearalenone (ZEN) are highly common mycotoxins in maize and maize-based products. This study aimed to report a time-resolved fluorescence immunochromatographic assay (TRFICA) developed using two idiotypic nanobodies for rapid, quantitative, and simultaneous detection of aflatoxin B (AFB) and ZEN in maize and its products. A novel Eu/Tb(III) nanosphere with enhanced fluorescence was prepared as a label and conjugated to anti-idiotypic nanobody (AIdnb) and monoclonal antibody (mAb). On the basis of nanosphere-antibody conjugation, two patterns of competitive time-resolved strip methods (AIdnb-TRFICA and mAb-TRFICA) were established and compared. The half inhibition concentration of AIdnb-TRFICA was 0.46 and 0.86 ng·mL for AFB and ZEN, which was 18.3- and 20.3-fold more sensitive than that of mAb-TRFICA for AFB and ZEN, respectively. Under optimal conditions, AIdnb-TRFICA for dual mycotoxin was established and provided a quantitative relationship ranging from 0.13 to 4.54 ng·mL for AFB and 0.20 to 2.77 ng·mL for ZEN, with a detection limit of 0.05 and 0.07 ng·mL in the buffer solution, respectively. AIdnb-TRFICA showed good recoveries (72.6%-106.6%) in samples and was applied to detect dual mycotoxin in maize samples with satisfying results. To the best of our knowledge, it is the first report about a time-resolved strip method based on AIdnbs for dual mycotoxin.
黄曲霉毒素和玉米赤霉烯酮（ZEN）是玉米及其制品中常见的真菌毒素。本研究旨在报道一种基于两种独特型纳米抗体的时间分辨荧光免疫层析法（TRFICA），用于快速、定量和同时检测玉米及其制品中的黄曲霉毒素 B（AFB）和 ZEN。制备了一种新型的具有增强荧光的 Eu/Tb(III)纳米球作为标记，并与抗独特型纳米抗体（AIdnb）和单克隆抗体（mAb）偶联。在此基础上，建立并比较了两种基于纳米球-抗体偶联的竞争时间分辨条带方法（AIdnb-TRFICA 和 mAb-TRFICA）。AIdnb-TRFICA 的半抑制浓度为 0.46 和 0.86ng·mL 时，对 AFB 和 ZEN 的检测限分别为 0.13 和 0.20ng·mL，对 AFB 和 ZEN 的灵敏度分别比 mAb-TRFICA 高 18.3 倍和 20.3 倍。在最佳条件下，建立了用于双真菌毒素的 AIdnb-TRFICA，并提供了 AFB 的定量关系范围为 0.13-4.54ng·mL，ZEN 的定量关系范围为 0.20-2.77ng·mL，在缓冲溶液中的检测限分别为 0.05 和 0.07ng·mL。AIdnb-TRFICA 在样品中的回收率良好（72.6%-106.6%），并应用于检测玉米样品中的双真菌毒素，结果令人满意。据我们所知，这是首次报道基于 AIdnbs 的双真菌毒素时间分辨条带方法。
