Tran Huynh Nhu, Nguyen Nguyen Binh, Ly Nguyễn Hoàng, Joo Sang-Woo, Vasseghian Yasser
Department of Chemistry, Soongsil University, Seoul, 06978, South Korea.
Department of Chemistry, Gachon University, Seongnam, 13120, South Korea.
Environ Pollut. 2023 Jan 15;317:120775. doi: 10.1016/j.envpol.2022.120775. Epub 2022 Nov 28.
A sensitive and stable substrate plays a vital role in the Raman spectroscopic techniques as an analytical method for detecting pesticides effectively from the environment. Enhancing signals from nanoparticles are weak and inconsistent in repeatability since analytes tend to degrade quickly under laser exposure. Herein, a novel substrate of Au@ZIF-67 is prepared on octahedral AuNPs by trapping pesticide molecules with small three-dimensional volumes by the flexibility of ZIF-67 for rapid detection with high sensitivity and stability. The two types of thiram and carbendazim pesticides, which are environmental pollutants that affect biodiversity, were successfully absorbed in Au@ZIF-67 nanostructures by adsorption-desorption equilibrium for analytical purposes in Raman spectroscopy. Spectra calculations of the thiram and carbendazim molecules on 8 atoms of Au using DFT were compared with the experimental data. The SERS enhancement factors for thiram and carbendazim were estimated to be 1.91 × 10 and 3.12 × 10, respectively, with the LOD values of trace amounts of ∼10 mol L. The novel substrate of Au@ZIF-67 is a propitious platform for detecting thiram and carbendazim in trace amounts, providing a helpful strategy for detecting residues with high performance in the environment at the laboratory and practical scales.
作为一种从环境中有效检测农药的分析方法，灵敏且稳定的基底在拉曼光谱技术中起着至关重要的作用。由于分析物在激光照射下容易快速降解，增强来自纳米颗粒的信号较弱且重复性不一致。在此，通过利用ZIF-67的柔韧性以小三维体积捕获农药分子，在八面体金纳米颗粒上制备了一种新型的Au@ZIF-67基底，用于高灵敏度和稳定性的快速检测。两种作为影响生物多样性的环境污染物的农药，福美双和多菌灵，通过吸附-解吸平衡成功吸附在Au@ZIF-67纳米结构中，用于拉曼光谱分析。使用密度泛函理论（DFT）对福美双和多菌灵分子在8个金原子上的光谱计算与实验数据进行了比较。福美双和多菌灵的表面增强拉曼散射（SERS）增强因子分别估计为1.91×10和3.12×10，痕量检测限约为10 mol L。新型的Au@ZIF-67基底是检测痕量福美双和多菌灵的有利平台，为在实验室和实际规模下高效检测环境中的残留物提供了一种有用的策略。
