State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Institute of Agro-Product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.
College of Agriculture and Biotechnology, Hunan University of Humanities, Science and Technology, Loudi 417000, China.
Food Chem. 2023 Feb 15;402:134487. doi: 10.1016/j.foodchem.2022.134487. Epub 2022 Oct 3.
A multi-functional nanoflares biosensor of spherical gold nanoparticle (Au NP) modified by fluorophore-labeled oligonucleotides (ONS) was designed for ultra-sensitive multi-target mycotoxin analysis in food. Au NP was densely modified with multiplex highly oriented hairpins of oligonucleotides (ONS), each ONS was hybridized to a reporter with a distinct fluorophore label and specifically affiliative to its corresponding mycotoxin target. The fluorescent signals of reporters were pre-quenched by Au NP based on ONS hairpin structures and recovered when exposed to ONS's targets. Excitation-emission matrix (EEM) fluorescence detection was performed in EX and EM wavelength of 200-800 nm. Heavily overlapping spectra of fluorophores, mycotoxins and backgrounds were resolved by alternative trilinear decomposition (ATLD) algorithm, pure spectra of specific fluorophore responding to mycotoxin target can be extracted out for quantitative analysis. Four mycotoxins (Aflatoxin B1, zearalenone, Fumonisins B1, ochratoxin A) were simultaneously quantified at extremely low level with limit of detection <0.02 μg kg, the average recovery accuracies were higher than 91.7 % in various matrices of cereals, nuts, edible oils. This study realized an important breakthrough of the application of nanoflares biosensor and maybe promising to be as an alternative strategy for onsite mycotoxins monitoring of food.
一种多功能的纳米级荧光生物传感器，由荧光标记寡核苷酸（ONS）修饰的球形金纳米粒子（Au NP）组成，用于食品中超敏多目标真菌毒素分析。Au NP 被高度修饰了多重定向发夹结构的寡核苷酸（ONS），每个 ONS 与具有独特荧光标记的报告分子杂交，并与相应的真菌毒素靶标特异性结合。当暴露于 ONS 的靶标时，基于 ONS 发夹结构的 Au NP 预先猝灭报告分子的荧光信号，然后恢复。在 200-800nm 的 EX 和 EM 波长下进行激发-发射矩阵（EEM）荧光检测。通过交替三线性分解（ATLD）算法解析荧光团、真菌毒素和背景的严重重叠光谱，可以提取出响应真菌毒素靶标的特定荧光团的纯光谱进行定量分析。四种真菌毒素（黄曲霉毒素 B1、玉米赤霉烯酮、伏马菌素 B1、赭曲霉毒素 A）在极低水平下同时被定量检测，检测限<0.02μg kg，在谷物、坚果、食用油等各种基质中的平均回收率均高于 91.7%。本研究实现了纳米级荧光生物传感器应用的重要突破，有望成为食品中真菌毒素现场监测的替代策略。
