Key Laboratory of Biotechnology and Bioresources Utilization of Ministry of Education, School of Life Sciences, Dalian Minzu University, Dalian, Liaoning 116600, People's Republic of China.
Dalian Inspection and Testing Certification Technical Service Center, Dalian, Liaoning 116021, People's Republic of China.
J Agric Food Chem. 2023 Dec 6;71(48):19121-19128. doi: 10.1021/acs.jafc.3c06962. Epub 2023 Nov 27.
Fumonisin B1 (FB1), as one of the highest toxicity mycotoxins, poses a serious threat to animal and human health, even at low concentrations. It is significant and challenging to develop a sensitive and reliable analytical device. Herein, a paper-based electrochemical aptasensor was designed utilizing tetrahedral DNA nanostructures (TDNs) to controllably anchor an aptamer (Apt), improving the recognition efficiency of Apt to its target. First, gold nanoparticles (AuNPs)@MXenes were used as a sensing substrate with good conductivity and modified on the electrode for immobilization of complementary DNA-TDNs (cDNA-TDNs). In the absence of FB1, numerous Apt-Au@Pt nanocrystals (NCs) was hybridized with cDNA and assembled on the sensing interface, which accelerated the oxidation of TMB with HO and produced a highly amplified differential pulse voltammetry (DPV) signal. When the target FB1 specifically bound to its Apt, the electrochemical signal was decreased by releasing the Apt-Au@Pt NCs from double-stranded DNA (dsDNA). On account of the strand displacement reaction by FB1 triggering, the aptasensor had a wider dynamic linear range (from 50 fg/mL to 100 ng/mL) with a lower limit of detection (21 fg/mL) under the optimized conditions. More impressively, the designed FB1 aptasensor exhibited satisfactory performance in corn and wheat samples. Therefore, the TDN-engineered sensing platform opens an effective approach for sensitive and accurate analysis of FB1, holding strong potential in food safety and public health.
伏马菌素 B1（FB1）是毒性最强的霉菌毒素之一，即使在低浓度下，也会对动物和人类健康构成严重威胁。开发一种灵敏可靠的分析设备具有重要意义和挑战性。在此，我们设计了一种基于纸的电化学适体传感器，利用四面体 DNA 纳米结构（TDN）可控地固定适体（Apt），提高 Apt 对其靶标的识别效率。首先，金纳米粒子（AuNPs）@MXenes 用作具有良好导电性的传感基底，并修饰在电极上，用于固定互补 DNA-TDN（cDNA-TDN）。在没有 FB1 的情况下，大量 Apt-Au@Pt 纳米晶（NCs）与 cDNA 杂交并组装在传感界面上，这加速了 TMB 在 HO 存在下的氧化，并产生了高度放大的差分脉冲伏安法（DPV）信号。当目标 FB1 特异性结合其 Apt 时，通过从双链 DNA（dsDNA）中释放 Apt-Au@Pt NCs，电化学信号降低。由于 FB1 触发的链置换反应，在优化条件下，该适体传感器具有更宽的动态线性范围（从 50 fg/mL 到 100 ng/mL），检测限（LOD）为 21 fg/mL。更令人印象深刻的是，所设计的 FB1 适体传感器在玉米和小麦样品中表现出令人满意的性能。因此，基于 TDN 的传感平台为 FB1 的灵敏准确分析开辟了一条有效途径，在食品安全和公共健康方面具有巨大潜力。
