摘要
本文综述了苯基脲类和磺酰脲类除草剂半抗原的设计原则、合成方法及影响因素等方面的研究进展。合成苯基脲类除草剂半抗原,在苯基脲类分子中引入可供结合用活性基团的位点主要有3种,即外部脲桥上的氮、内部脲桥上的氮以及直接在苯环上。研究表明,在外部脲桥上的氮连接亚甲基基团是最理想的半抗原。合成磺酰脲类除草剂半抗原有保留苯环部分、保留杂环部分和保留磺酰脲分子全部特征部分3种方法。经比较研究,保留苯环特征部分的半抗原要比保留磺酰脲全部特征部分的半抗原产生的抗体有更高的亲和力。间隔臂长度是半抗原设计的一个重要因素。间隔臂长(5个亚甲基)的半抗原一般要比间隔臂短的半抗原更能产生理想的免疫结果。在建立酶联免疫法中选择包被/示踪半抗原时,选用比免疫用半抗原更不被抗体识别的半抗原做包被/示踪半抗原。示踪半抗原亲和力的适度减少,被分析物所需的量可以减少,可以进一步提高分析的灵敏度,降低检测限。
Immune assay is one of the recently developed analytical methods of pesticide residue. The synthesis of hapten is a key factor in establishing an immunoassay. This article summarized the study progress of the hapten for phenylurea and sulfonylurea herbicides including the idea of synthesis and the influencing factors. To maximize selective target molecule recognition, the immunizing hapten was designed to represent a near-perfect mimic of the target molecule in structure, electronic, and hydrophobic properties. From the three potential locations for handle attachment（the terminal urea nitrogen, the internal urea nitrogen, and directly on the aromatic ring system） the compounds with an extension of the terminal N-methyl group with innocuous methylene groups, provide the most perfect mimic of the phenylurea herbicide structure. The antibodies with much higher affinity for sulfonylurea herbicides were generated using the haptens that had only a phenyl moiety of the corresponding sulfonylurea herbicides, compared to those obtained with a hapten consisting of the complete molecule. In general, longer （five methylene） handle provided better test results than the shorter handle, suggesting that handle length and/or flexibility are important factors in assay utility. Compared to the hapten used for immunization, the hapten for enzyme label or for coating antigen should be less recognized by the antibodies. This moderately decreased affinity relative to the analyte could lower the amounts of analyte required for the equilibrium under working conditions. In this way the assay sensitivity and determination limit could be improved.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2008年第5期1697-1704,共8页
Journal of Agro-Environment Science
基金
国家自然科学基金项目(20447003)
