Abstract:
Deoxynivalenol (DON) is a common mycotoxin that contaminates cereals. Therefore, the development of sensitive and efficient detection methods for DON is essential to guarantee food safety and human health. In this study, an enzyme cascade amplification-based immunoassay (ECAIA) using a dual-functional alkaline phosphatase-linked single-chain fragment variable fusion tracer (scFv-ALP) and MnO2 nanosheets was established for DON detection. The scFv-ALP effectively catalyzes the hydrolysis of ascorbyl-2-phosphate (AAP) to produce ascorbic acid (AA). This AA subsequently interacts with MnO2 nanosheets to initiate a redox reaction that results in the loss of oxidizing properties of MnO2. In the absence of ALP, MnO2 nanosheets can oxidize 3,3\',5,5\'-tetramethylbenzidine (TMB) to produce the blue oxidized product of TMB, which exhibits a signal at a wavelength of 650 nm for quantitative analysis. After optimization, the ECAIA had a limit of detection of 0.45 ng/mL and a linear range of 1.2-35.41 ng/mL. The ECAIA exhibited good accuracy in recovery experiments and high selectivity for DON. Moreover, the detection results of the actual corn samples correlated well with those from high-performance liquid chromatography. Overall, the proposed ECAIA based on the scFv-ALP and MnO2 nanosheets was demonstrated as a reliable tool for the detection of DON in corn samples.
摘要:
脱氧雪腐镰刀菌烯醇(DON)是一种常见的污染谷物的霉菌毒素。因此,开发灵敏、高效的DON检测方法对保障食品安全和人类健康至关重要。在这项研究中,使用双功能碱性磷酸酶连接的单链片段可变融合示踪剂(scFv-ALP)和MnO2纳米片建立了基于酶级联扩增的免疫测定(ECAIA)用于DON检测。scFv-ALP有效地催化抗坏血酸-2-磷酸酯(AAP)的水解以产生抗坏血酸(AA)。该AA随后与MnO2纳米片相互作用以引发导致MnO2的氧化性质丧失的氧化还原反应。如果没有ALP,MnO2纳米片可以氧化3,3',5,5'-四甲基联苯胺(TMB)产生TMB的蓝色氧化产物,其在650nm波长处表现出用于定量分析的信号。优化后,ECAIA的检测限为0.45ng/mL,线性范围为1.2~35.41ng/mL.ECAIA在回收实验中表现出良好的准确性和对DON的高选择性。此外,实际玉米样品的检测结果与高效液相色谱法的检测结果具有良好的相关性。总的来说,基于scFv-ALP和MnO2纳米片的拟议ECAIA被证明是检测玉米样品中DON的可靠工具。