Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food poisoning, Beijing Center for Disease Prevention and Control, Beijing 100013, China.
State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China.
ACS Sens. 2021 Jun 25;6(6):2129-2135. doi: 10.1021/acssensors.1c00560. Epub 2021 Jun 3.
Rapid screening monofluoroacetic acid (FAcOH) is responsible for preventing chemical poisoning and food safety events. Whereas surface enhanced Raman scattering (SERS) spectra is an effective tool for detecting forbidden chemicals, it is difficult to directly detect FAcOH due to its small Raman scattering cross section as well as weak adsorption on SERS substrates. In this work, the metal phenolic supramolecular networks (MPNs, i.e., the tannic acid and Fe complex) were fabricated on the commercial nanoanodic aluminum oxide film (NAAO) for assisting in situ chemical deposition highly uniform Ag nanostructure over large areas (the NAAO@AgNS). The low cost and simple fabrication process made the NAAO@AgNS a single-use consumable. For FAcOH detection, a specific derivative reaction between FAcOH and thiosalicylic acid (TSA) was introduced. By taking TSA as the Raman probe, its SERS signal attenuated constantly with the increasing amount of FAcOH. For improving quantitative accuracy, thiocyanate (SCN) was introduced on the NAAO@AgNS as an internal standard; thus, the characteristic peak intensity ratios associated with TSA and SCN (/) were fitted to the concentration of FAcOH. It was demonstrated that the SERS assay achieved good sensitivity and selection toward FAcOH with the limit of quantitation (LOD) as low as 50 nmol L. The NAAO@AgNS featured with highly sensitive, uniform, and consistent SERS performances could easily extend to wide SERS applications.
快速筛选单氟乙酸（FAcOH）可防止化学中毒和食品安全事件。表面增强拉曼散射（SERS）光谱是检测违禁化学品的有效工具，但由于 FAcOH 的拉曼散射截面小，在 SERS 基底上的吸附较弱，因此很难直接检测到 FAcOH。在这项工作中，金属酚超分子网络（MPNs，即单宁酸和 Fe 配合物）被制备在商业纳米阳极氧化铝膜（NAAO）上，以协助在原位化学沉积大面积高度均匀的 Ag 纳米结构（NAAO@AgNS）。该方法成本低，制备工艺简单，使 NAAO@AgNS 成为一次性消耗品。为了检测 FAcOH，引入了 FAcOH 与巯基水杨酸（TSA）之间的特定衍生反应。通过将 TSA 作为拉曼探针，其 SERS 信号随 FAcOH 量的增加而不断衰减。为了提高定量准确性，在 NAAO@AgNS 上引入了硫氰酸根（SCN）作为内标；因此，与 TSA 和 SCN 相关的特征峰强度比（/）被拟合到 FAcOH 的浓度。结果表明，该 SERS 分析方法对 FAcOH 具有良好的灵敏度和选择性，检出限（LOD）低至 50nmol/L。具有高灵敏度、均匀一致的 SERS 性能的 NAAO@AgNS 可以很容易地扩展到广泛的 SERS 应用中。
