Lan Meijing, Guo Yirong, Zhao Ying, Liu Yihua, Gui Wenjun, Zhu Guonian
Institute of Pesticide and Environmental Toxicology, Zhejiang University, 310058 Hangzhou, China.
Institute of Pesticide and Environmental Toxicology, Zhejiang University, 310058 Hangzhou, China.
Anal Chim Acta. 2016 Sep 28;938:146-55. doi: 10.1016/j.aca.2016.07.044. Epub 2016 Aug 2.
This paper describes the development of a new multiplex immunoassay for simultaneous detection of seven pesticides (triazophos, methyl-parathion, fenpropathrin, carbofuran, thiacloprid, chlorothalonil, and carbendazim). Sixteen pairs of pesticide antibodies and antigens were screened for reactivity and cross-reaction. A microarray chip consisting of seven antigens immobilized on a nitrocellulose membrane was then constructed. Nanogold was employed for labeling and signal amplification to obtain a sensitive colorimetric immunoassay. The direct and indirect detection formats were further compared using primary antibody-gold and secondary antibody-gold conjugates as tracers. An integrated 7-plex immunochip assay based on the indirect model was established and optimized. The detection limits for the pesticides were 0.02-6.45 ng mL(-1), which meets detection requirements for pesticide residues. Naked-eye assessment showed the visual detection limits of the assay ranged from 1 to 100 ng mL(-1). Spiked recovery results demonstrated that the immunochip assay had potential for multi-analysis of pesticide residues in vegetables and fruits. The proposed microarray methodology is a flexible and versatile tool, which can be applied to other competitive multiplex immunoassays for small molecular compounds.
本文描述了一种用于同时检测七种农药（三唑磷、甲基对硫磷、甲氰菊酯、克百威、噻虫啉、百菌清和多菌灵）的新型多重免疫分析方法的开发。筛选了16对农药抗体和抗原的反应性及交叉反应性。然后构建了一种由固定在硝酸纤维素膜上的七种抗原组成的微阵列芯片。采用纳米金进行标记和信号放大，以获得灵敏的比色免疫分析方法。使用一抗-金和二抗-金缀合物作为示踪剂，进一步比较了直接和间接检测形式。建立并优化了基于间接模式的集成7重免疫芯片分析方法。这些农药的检测限为0.02 - 6.45 ng mL⁻¹，满足农药残留的检测要求。肉眼评估表明该分析方法的目视检测限为1至100 ng mL⁻¹。加标回收率结果表明，免疫芯片分析方法具有对蔬菜和水果中农药残留进行多分析的潜力。所提出的微阵列方法是一种灵活通用的工具，可应用于其他小分子化合物的竞争性多重免疫分析。
