Wang Shuo, Zhang Can, Zhang Yan
Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin Key Laboratory of Food Nutrition and Safety, Tianjin University of Science and Technology, Tianjin, China.
Methods Mol Biol. 2009;504:237-52. doi: 10.1007/978-1-60327-569-9_15.
In recent years, immunochromatographic lateral flow test strips are used as a popular diagnostic tool. There are two formats (noncompetitive and competitive) in gold-based immunoassay. Noncompetitive gold-based immunoassay also called sandwich assay is applied for the detection of large molecular mass. For small molecular mass such as pesticide, competitive format of lateral flow colloidal gold-based immunoassay is described in this chapter. The preparation of gold colloidal and the conjugation between antibody and gold colloidal are described. Hi-flow plus nitrocellulose membranes are separately coated with goat anti-rabbit IgG (control line) and hapten-OVA conjugate (test line). Thus, the degree of intensity of color of the test line is the reverse of the concentration of pesticide in the sample and the visual result is immediately observable. Colloidal gold-based immunoassay can also be applied for multianalysis in one test strip if the detected targets show different physico-chemical properties and their haptens show great differences in chemical structure.
近年来，免疫层析侧向流动试纸条作为一种流行的诊断工具被广泛使用。基于金的免疫测定有两种形式（非竞争性和竞争性）。非竞争性基于金的免疫测定也称为夹心测定，用于检测大分子质量物质。对于小分子质量物质，如农药，本章介绍了侧向流动胶体金免疫测定的竞争形式。描述了金胶体的制备以及抗体与金胶体之间的偶联。高流量加硝酸纤维素膜分别用山羊抗兔IgG（控制线）和半抗原-卵清蛋白偶联物（测试线）包被。因此，测试线颜色的强度程度与样品中农药的浓度呈反比，视觉结果可立即观察到。如果检测的目标显示出不同的物理化学性质且它们的半抗原在化学结构上有很大差异，基于胶体金的免疫测定也可用于在一个试纸条上进行多重分析。
