School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China; Academy of Contemporary Food Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Guangzhou 510006, China; Engineering and Technological Research Centre of Guangdong Province on Intelligent Sensing and Process Control of Cold Chain Foods, & Guangdong Province Engineering Laboratory for Intelligent Cold Chain Logistics Equipment for Agricultural Products, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China.
School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China; Academy of Contemporary Food Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Guangzhou 510006, China; Engineering and Technological Research Centre of Guangdong Province on Intelligent Sensing and Process Control of Cold Chain Foods, & Guangdong Province Engineering Laboratory for Intelligent Cold Chain Logistics Equipment for Agricultural Products, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China; Food Refrigeration and Computerized Food Technology (FRCFT), Agriculture and Food Science Centre, University College Dublin, National University of Ireland, Belfield, Dublin 4, Ireland.
Spectrochim Acta A Mol Biomol Spectrosc. 2023 Dec 5;302:123121. doi: 10.1016/j.saa.2023.123121. Epub 2023 Jul 8.
Aflatoxin B1 (AFB1) contamination severely threatens human and animal health, it is thus critical to construct a strategy for its rapid, accurate, and visual detection. Herein, a multimodal biosensor was proposed based on CRISPR/Cas12a cleaved G-quadruplex (G4) for AFB1 detection. Briefly, specific binding of AFB1 to the aptamer occupied the binding site of the complementary DNA (cDNA), and cDNA then activated Cas12a to cleave G4 into fragments. Meanwhile, the intact G4-DNAzyme could catalyze 3, 3', 5, 5'-tetramethylbenzidine (TMB) to form colourimetric/SERS/fluorescent signal-enhanced TMBox, and the yellow solution produced by TMBox under acidic conditions could be integrated with a smartphone application for visual detection. The colourimetric/SERS/fluorescent biosensor yielded detection limits of 0.85, 0.79, and 1.65 pg·mL, respectively, and was applied for detecting AFB1 in peanut, maize, and badam samples. The method is suitable for visual detection in naturally contaminated peanut samples and has prospective applications in the food industry.
黄曲霉毒素 B1（AFB1）污染严重威胁着人类和动物的健康，因此构建其快速、准确、可视化检测的策略至关重要。本文基于 CRISPR/Cas12a 切割 G-四链体（G4）构建了一种用于 AFB1 检测的多模态生物传感器。简要地说，AFB1 与适体的特异性结合占据了互补 DNA（cDNA）的结合位点，然后 cDNA 激活 Cas12a 将 G4 切割成片段。同时，完整的 G4-DNA 酶可以催化 3,3',5,5'-四甲基联苯胺（TMB）形成比色/SERS/荧光信号增强的 TMBox，并且在酸性条件下 TMBox 产生的黄色溶液可以与智能手机应用程序集成进行可视化检测。比色/SERS/荧光生物传感器的检测限分别为 0.85、0.79 和 1.65 pg·mL-1，并应用于花生、玉米和巴达姆样品中 AFB1 的检测。该方法适用于天然污染花生样品的可视化检测，具有广阔的食品工业应用前景。
