China National Tobacco Quality Supervision and Test Center, Zhengzhou 450001, China.
Yunnan Institute of Tobacco Quality Inspection & Supervision, Kunming 650106, China.
Anal Methods. 2022 Nov 10;14(43):4370-4376. doi: 10.1039/d2ay01374f.
Iprodione is a dicarboximide fungicide that is widely used in agriculture around the world. A reliable and rapid detection method is needed for the on-site monitoring of iprodione residues in a variety of agricultural products. Herein, a colloidal gold immunochromatographic test strip was developed based on a selected coating antigen and a specific monoclonal antibody against iprodione. The particle size of colloidal gold, the preparation technique of the conjugate pad, the composition of the loading buffer, and the extraction solvent were comprehensively optimized for the test strip. A cut-off value of 0.9 mg kg (50 ng mL) and a visual limit of detection of 0.09 mg kg (5 ng mL) were achieved in a complex matrix of tobacco. No cross-reactivity was observed for iprodione metabolite and four other widely used pesticides during tobacco growth. Furthermore, the developed colloidal gold immunochromatographic test strip was applied to determine iprodione residues in tobacco samples, and the obtained results were in good agreement with those obtained by liquid chromatography tandem mass spectrometry. Additionally, the test strip was found to be stable afterlong-term storage at 37 °C for two months. The developed colloidal gold immunochromatographic test strip showed excellent accuracy, sensitivity, specificity, and stability, therefore, it is suitable for the rapid detection of iprodione residues in complex matrices.
抑霉唑是一种广泛应用于世界范围内农业的二羧酰亚胺类杀菌剂。需要开发一种可靠且快速的检测方法，以便对各种农产品中抑霉唑残留进行现场监测。本文基于筛选出的包被抗原和针对抑霉唑的特异性单克隆抗体，建立了胶体金免疫层析检测方法。综合优化了胶体金粒径、标记垫制备技术、加载缓冲液组成和提取溶剂，实现了在复杂的烟草基质中检测抑霉唑的截取值为 0.9 mg kg（50ng/mL），肉眼检出限为 0.09 mg kg（5ng/mL）。在烟草生长过程中，该方法对抑霉唑代谢物和其他四种常用农药均无交叉反应。此外，该胶体金免疫层析检测方法还用于测定烟草样品中的抑霉唑残留，其结果与液相色谱-串联质谱法的结果一致。此外，经过两个月在 37°C 下的长期储存，检测条仍保持稳定。所建立的胶体金免疫层析检测方法具有良好的准确性、灵敏度、特异性和稳定性，适用于复杂基质中抑霉唑残留的快速检测。
