a Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine , China Agricultural University, Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, Beijing Laboratory for Food Quality and Safety , Beijing , People's Republic of China.
b China Animal Health and Epidemiology Center , Qingdao , People's Republic of China.
Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2018 Dec;35(12):2434-2442. doi: 10.1080/19440049.2018.1539251. Epub 2018 Nov 19.
A time-resolved fluorescent immunochromatographic assay (TRFICA) was successfully developed for the sensitive, simultaneous, and quantitative detection of aflatoxin B (AFB1) and zearalenone (ZEN) in Chinese herbal medicines. Eu-nanospheres (EuNPs) with unique optical properties increased the stability and sensitivity of the immunochromatographic assay. To obtain stable quantitative results, we applied a three-label system in which monoclonal antibodies for AFB1 and ZEN were conjugated to the EuNPs as detection probes on the test line (T line), and EuNP-labelled chicken IgY conjugates acted as the reference on the control line (C line). The fluorescence intensities of the T and C lines were recorded, and the T/C ratio was employed as the quantitative signal for the elimination of strip variation and matrix effects. The parameters that affected the TRFICA were optimised. Under optimal conditions, the established TRFICA gave good linear ranges from 0.60 μg/kg to 3.92 μg/kg for AFB1 and from 0.40 μg/kg to 1.28 μg/kg for ZEN. The limits of detection for AFB1 and ZEN were as low as 0.60 and 0.40 μg/kg, respectively, in Chinese herbal medicines Semen coicis, Rhizoma dioscoreae, and Platycodon grandiflorus, respectively. The average recoveries of the spiked samples were 73%-95% for AFB1 and 75.83%-90% for ZEN, both with a relative standard deviation of < 9.08%. The results of 15 actual samples detected by the developed TRFICA showed a satisfactory correlation with those of ultra-performance liquid chromatography tandem mass spectrometry. Therefore, the TRFICA is a simple, rapid, and sensitive approach to quantitatively detect mycotoxins in Chinese herbal medicines.
建立了一种时间分辨荧光免疫层析法（TRFICA），用于灵敏、同时和定量检测中草药中的黄曲霉毒素 B（AFB1）和玉米赤霉烯酮（ZEN）。具有独特光学性质的铕纳米球（EuNPs）提高了免疫层析法的稳定性和灵敏度。为了获得稳定的定量结果，我们应用了三标记系统，其中 AFB1 和 ZEN 的单克隆抗体被共轭到 EuNPs 上作为检测探针在测试线上（T 线），EuNP 标记的鸡 IgY 共轭物作为对照在控制线（C 线）上。记录 T 线和 C 线的荧光强度，并将 T/C 比值作为定量信号，以消除条带变化和基质效应。优化了影响 TRFICA 的参数。在最佳条件下，所建立的 TRFICA 对 AFB1 的线性范围为 0.60μg/kg 至 3.92μg/kg，对 ZEN 的线性范围为 0.40μg/kg 至 1.28μg/kg。在薏苡仁、山药和桔梗等中草药中，AFB1 和 ZEN 的检测限分别低至 0.60 和 0.40μg/kg。AFB1 和 ZEN 的平均回收率分别为 73%-95%和 75.83%-90%，相对标准偏差均小于 9.08%。用所开发的 TRFICA 检测 15 个实际样品的结果与超高效液相色谱串联质谱法的结果具有令人满意的相关性。因此，TRFICA 是一种简单、快速、灵敏的定量检测中草药中真菌毒素的方法。
