Dithiocarbamates (DTCs) are a group of fungicides with various toxicities, and are widely used in agriculture. Currently, most of the official DTC detection methods cannot identify residues of individual DTCs, such as dimethyldithiocarbamates (DMDCs), ethylene-bis-dithiocarbamates (EBDCs) and propylene-bis-dithiocarbamates (PBDCs), on crops. Surface-enhanced Raman scattering (SERS) provides fingerprint recognition from the scattering spectra of molecular vibrations, and it has excellent potential as a primary qualitative screening tool. In this study, glancing angle deposition (GLAD) was used to fabricate SERS substrates with Ag@Au alloyed nanorods to provide cost-effective and rapid detection, and an optimal procedure for extracting DTC residues on the surface of crops was proposed. This study verified that under ordinary Raman spectroscopy conditions (excitation light, 785 nm; power, 20 mW; and integration, 3 min), extraction with tepid water and the addition of 0.1% sodium chloride can enable the detection of thiram (a DMDC), propineb (a PBDC) and mancozeb (an EBDC) on crops at trace concentrations of 0.05, 0.1 and 0.2 ppm, respectively, even on crops containing high levels of endogenous sulfides, such as cauliflower and white radish. Using the developed SERS-active substrate, qualitative and semi-quantitative results can be obtained by employing the specific characteristic peaks of the Raman scattering patterns to distinguish three types of DTCs. The method proposed in this study offers the advantages of simple operation, few consumables, high safety, and no interference from the matrix. Hence, this study provides an auxiliary approach for DTC detection.

二硫代氨基甲酸酯（DTC）是一组具有各种毒性的杀真菌剂，广泛用于农业。当前，大多数官方DTC检测方法无法识别作物上单个DTC的残留物，例如二甲基二硫代氨基甲酸酯（DMDC），乙烯-双-二硫代氨基甲酸酯（EBDC）和丙烯-双-二硫代氨基甲酸酯（PBDC）。表面增强拉曼散射（SERS）可从分子振动的散射光谱中识别指纹，并且作为主要的定性筛选工具，它具有极好的潜力。在这项研究中，掠射角沉积（GLAD）用于制备具有Ag @ Au合金纳米棒的SERS基底，以提供具有成本效益的快速检测，并提出了一种提取农作物表面DTC残留物的最佳方法。这项研究证实，在普通拉曼光谱条件下（激发光为785 nm；功率为20 mW；积分时间为3分钟），用温水萃取并添加0.1％氯化钠可以检测到thiram（一种DMDC）。 ，propineb（PBDC）和mancozeb（EBDC）分别在痕量浓度为0.05、0.1和0.2 ppm的作物上，即使在含有高水平内源性硫化物（例如花椰菜和白萝卜）的作物上也是如此。使用开发的SERS活性底物，可以通过使用拉曼散射图的特定特征峰来区分三种类型的DTC来获得定性和半定量结果。本研究提出的方法具有操作简单，耗材少，安全性高，不受基质干扰的优点。因此，