Zhou Weilu, Kong Weijun, Dou Xiaowen, Zhao Ming, Ouyang Zhen, Yang Meihua
Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100193, China; School of Pharmacy, Jiangsu University, Zhenjiang, Jiangsu 212013, China.
Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100193, China.
J Chromatogr B Analyt Technol Biomed Life Sci. 2016 Jun 1;1022:102-108. doi: 10.1016/j.jchromb.2016.04.016. Epub 2016 Apr 9.
An aptamer based lateral flow strip based on competitive format was developed for on-site rapid detection of ochratoxin A (OTA) in Astragalus membranaceus. Some crucial parameters that might influence the sensitive detection, such as the characterization of the colloidal gold, size and shape of gold nanoparticles (AuNPs), amount of AuNPs-aptamer conjugate, migration rate and the addition amount of methanol, were investigated to provide the optimum assay performance. To perform the test, 1g sample was extracted with 2.5mL of methanol-water (80:20, v/v) and diluted by 4-fold running buffer to eliminate the matrix and methanol interferences. Under optimized conditions, the aptamer-based assay showed a visual limit of detection (LOD) of 1ngmL(-1), and with no significant cross-reactivity with several homologous toxins. The whole detection could be completed within 15min without special equipment because of available visual results. One out of nine A. membranaceus samples was found to be positive of OTA, which was in a good agreement with those obtained from LC-MS/MS analysis. The results demonstrated that the aptamer-based lateral flow assay could be used as a rapid, reliable, cost-effective and robust on-site screening technique for mycotoxins at trace level in complex matrices without special instrumentation.
开发了一种基于适配体的竞争型侧向流动试纸条，用于黄芪中赭曲霉毒素A（OTA）的现场快速检测。研究了一些可能影响灵敏检测的关键参数，如胶体金的特性、金纳米颗粒（AuNPs）的大小和形状、AuNPs-适配体缀合物的量、迁移率以及甲醇的添加量，以提供最佳的检测性能。进行检测时，将1g样品用2.5mL甲醇-水（80:20，v/v）提取，并用4倍运行缓冲液稀释，以消除基质和甲醇干扰。在优化条件下，基于适配体的检测方法的目视检测限（LOD）为1ngmL(-1)，与几种同源毒素无明显交叉反应。由于结果可视，整个检测无需特殊设备即可在15分钟内完成。九个黄芪样品中有一个被检测出OTA呈阳性，这与液相色谱-串联质谱（LC-MS/MS）分析结果高度一致。结果表明，基于适配体的侧向流动检测方法可作为一种快速、可靠、经济高效且强大的现场筛选技术，用于在复杂基质中痕量水平的霉菌毒素检测，无需特殊仪器。
