Food Laboratory of Zhongyuan, Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing 100193, China.
Food Laboratory of Zhongyuan, Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing 100193, China.
Food Chem. 2024 Aug 1;448:139127. doi: 10.1016/j.foodchem.2024.139127. Epub 2024 Mar 23.
To address the food safety issues caused by toxins, we established a fluorescent copper nanocluster biosensor based on magnetic aptamer for the visual and quantitative detection of ZEN. Specifically, we utilized the docking-aided rational tailoring (DART) strategy to analyze intermolecular force and interaction sites between zearalenone (ZEN) and the aptamer, and optimize the long-chain aptamer step by step to enhance the binding affinity by 3.4 times. The magnetic bead-modified aptamer underwent conformational changes when competing with complementary sequences to bind with ZEN. Then, the released complementary sequences will be amplified in template-free mode with the presence of the terminal deoxynucleotidyl transferase (TdT), and generating T-rich sequences as the core sequences for the luminescence of copper nanoclusters. The luminescence could be visualized and quantitatively detected through ultraviolet irradiation. The proposed label-free aptasensor exhibited high sensitivity and specificity, with a low limit of detection (LOD) of 0.1 ng/mL.
为了解决由毒素引起的食品安全问题，我们建立了一种基于磁性适体的荧光铜纳米簇生物传感器，用于可视化和定量检测 ZEN。具体来说，我们利用对接辅助合理剪裁（DART）策略分析了玉米赤霉烯酮（ZEN）与适体之间的分子间力和相互作用位点，并逐步优化长链适体，使其结合亲和力提高了 3.4 倍。当与互补序列竞争与 ZEN 结合时，经磁珠修饰的适体发生构象变化。然后，在末端脱氧核苷酸转移酶（TdT）的存在下，以无模板的方式扩增释放的互补序列，并生成富含 T 的序列作为铜纳米簇发光的核心序列。通过紫外光照射可以可视化和定量检测发光。所提出的无标记适体传感器具有高灵敏度和特异性，检测限（LOD）低至 0.1ng/mL。
