School of Food Science and Nutrition, University of Leeds, Leeds LS2 9JT, UK.
Biosensors (Basel). 2021 Jan 8;11(1):18. doi: 10.3390/bios11010018.
Fumonisin B1 (FB1), a mycotoxin classified as group 2B hazard, is of high importance due to its abundance and occurrence in varied crops. Conventional methods for detection are sensitive and selective; however, they also convey disadvantages such as long assay times, expensive equipment and instrumentation, complex procedures, sample pretreatment and unfeasibility for on-site analysis. Therefore, there is a need for quick, simple and affordable quantification methods. On that note, aptamers (ssDNA) are a good alternative for designing specific and sensitive biosensing techniques. In this work, the assessment of the performance of two aptamers (40 and 96 nt) on the colorimetric quantification of FB1 was determined by conducting an aptamer-target incubation step, followed by the addition of gold nanoparticles (AuNPs) and NaCl. Although MgCl and Tris-HCl were, respectively, essential for aptamer 96 and 40 nt, the latter was not specific for FB1. Alternatively, the formation of Aptamer (96 nt)-FB1-AuNP conjugates in MgCl exhibited stabilization to NaCl-induced aggregation at increasing FB1 concentrations. The application of asymmetric flow field-flow fractionation (AF4) allowed their size separation and characterization by a multidetection system (UV-VIS, MALS and DLS online), with a reduction in the limit of detection from 0.002 µg/mL to 56 fg/mL.
伏马菌素 B1（FB1）是一种真菌毒素，被归类为 2B 类危害物，因其在各种作物中的丰富存在而具有重要意义。传统的检测方法具有灵敏度和选择性；然而，它们也存在一些缺点，如检测时间长、设备和仪器昂贵、操作复杂、样品预处理繁琐以及不适合现场分析等。因此，需要开发快速、简单和经济实惠的定量方法。在此背景下，适体（ssDNA）是设计特异性和高灵敏度生物传感技术的一种很好的选择。在这项工作中，通过进行适体-靶标孵育步骤，随后加入金纳米粒子（AuNPs）和 NaCl，评估了两种适体（40 和 96 个核苷酸）在 FB1 比色定量中的性能。尽管 MgCl 和 Tris-HCl 分别是适体 96 和 40 个核苷酸所必需的，但后者对 FB1 并不具有特异性。相反，在 MgCl 中形成的 Aptamer（96 nt）-FB1-AuNP 缀合物在 FB1 浓度增加时表现出对 NaCl 诱导聚集的稳定性。不对称流场流分离（AF4）的应用允许通过多检测系统（UV-VIS、MALS 和 DLS 在线）对其进行尺寸分离和表征，检测限从 0.002 µg/mL 降低至 56 fg/mL。
