School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China.
Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan 250062, China.
Food Chem. 2021 May 15;344:128570. doi: 10.1016/j.foodchem.2020.128570. Epub 2020 Nov 7.
Novel SERS substrates is urgently in demand for rapid and sensitive analysis of toxic agrochemicals from food. In this work, a monodispersed tungsten disulfide quantum dots modified silver nanosphere (Ag@WSQD) was prepared and used as SERS substrate. Ag@WSQD generated uniform and stable SERS signals within 2 min, displaying great promise in "mixing and reading" detection. Compared to unmodified colloidal silver nanoparticles, 4 times higher analytical enhancement factor was found in Ag@WSQD. Density functional theory calculation verified the enhanced charge transfer within the coupling systems of molecule-Ag@WSQD. Besides, the unique surface properties are beneficial for the enrichment of specific molecule. Both the chemical extraction and enhanced charge transfer contributes to rapid and sensitive SERS detection of Ag@WSQD. A "mixing and reading" SERS method for thiram from honey and four kinds of juice was developed from Ag@WSQD, showing great promise for rapid and direct SERS detection for toxic agrochemicals and further applications.
新型 SERS 基底对于快速、灵敏地分析食品中有毒农用化学品非常迫切。本工作制备了单分散二硫化钨量子点修饰的银纳米球（Ag@WSQD），并将其用作 SERS 基底。Ag@WSQD 在 2 分钟内产生均匀且稳定的 SERS 信号，在“混合读取”检测中具有很大的应用前景。与未修饰的胶体银纳米粒子相比，在 Ag@WSQD 中发现了 4 倍更高的分析增强因子。密度泛函理论计算验证了分子-Ag@WSQD 耦合体系中电荷转移的增强。此外，独特的表面性质有利于特定分子的富集。化学萃取和增强的电荷转移都有助于 Ag@WSQD 对 thiram 的快速灵敏 SERS 检测。基于 Ag@WSQD 开发了一种用于蜂蜜和四种果汁中 thiram 的“混合读取” SERS 方法，为快速、直接检测有毒农用化学品及其进一步应用提供了广阔的前景。
