State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, China.
State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, China.
Colloids Surf B Biointerfaces. 2020 Jun;190:110940. doi: 10.1016/j.colsurfb.2020.110940. Epub 2020 Mar 4.
Herein, we constructed an aptamer-based sensor for the sensitive and highly specific detection of Shigella sonnei via surface enhanced Raman spectroscopy (SERS) analysis. A composite material integrated of the Raman active 4-MBA ligand of the Eu-complex and citrate-stabilized Au nanoparticles (cit-Au NPs) was synthesized and served as both active substrate and Raman reporter. Aptamers targeted to S. Sonnei was then modified onto the surface of this dual-functional material. With the introduction of S. Sonnei, aptamer bound with target with high affinity and specificity, leaving the dual-functional material onto the bacteria. The SERS intensity response showed a strong positive linear correlation (R = 0.9956) with increasing concentrations of S. sonnei (ranging from 10 to 10 cfu/mL). High specificity was achieved at Shigella species (S. dysenteriae, S. flexneri, S. boydii) and other common bacteria (Salmonella typhimurium, Staphylococcus aureus and Escherichia coli). When applied in real samples, the approach showed recoveries from 92.6 to 103.8 %. The designed approach holds great potential for the construction of various aptasensors for the effective and convenient detection of different food hazards.
在此，我们构建了一种基于适体的传感器，通过表面增强拉曼光谱（SERS）分析，对宋内志贺氏菌进行灵敏、高特异性的检测。合成了一种复合材料，其中包含 Eu 配合物的拉曼活性 4-MBA 配体和柠檬酸盐稳定的金纳米粒子（cit-Au NPs），既作为活性基底，又作为拉曼报告分子。然后，将针对 S. Sonnei 的适体修饰到这种双功能材料的表面。随着 S. Sonnei 的引入，适体与靶标以高亲和力和特异性结合，使双功能材料留在细菌上。SERS 强度响应与 S. sonnei 的浓度呈强正线性相关（R=0.9956）（范围从 10 到 10 cfu/mL）。该方法在志贺氏菌属（痢疾志贺氏菌、福氏志贺氏菌、鲍氏志贺氏菌）和其他常见细菌（鼠伤寒沙门氏菌、金黄色葡萄球菌和大肠杆菌）中具有高特异性。在实际样品中的应用表明，该方法的回收率为 92.6%至 103.8%。该设计方法为构建各种适体传感器，用于有效、方便地检测不同的食品安全危害物具有很大的潜力。
