基于单克隆抗体的胶体金试纸条检测水产品中甲霜灵的残留

为了建立检测水产品中抗水霉药物甲霜灵残留的快速初筛方法,采用基于单克隆抗体技术的胶体金标记检测水产品中甲霜灵残留。甲霜灵单克隆抗体为IgG1,Kappa型;重链50 ku,轻链20 ku,分子质量约为150 ku;亲和力常数为2.46×10⁹ L/mol;IC₅₀为59.57 ng/mL。利用甲霜灵单克隆抗体作为金垫,甲霜灵-牛血清白蛋白偶联物及羊抗鼠IgG作为检测线与质控线,制备了甲霜灵胶体金免疫层析试纸条。测定结果显示:胶体金试纸条在甲霜灵质量浓度为5 mg/mL时可检出,与恩诺沙星、磺胺甲恶唑、氟苯尼考、呋喃唑酮、吡喹酮、强力霉素、孔雀石绿和亚甲基蓝等8种药物均无交叉反应。利用试纸条对草鱼(Ctenopharyngodon idella)、花蛤(Ruditapes philippinarum)、凡纳滨对虾(Litopenaeus vannamei)等水产品样品进行测试,在草鱼、凡纳滨对虾样品最低检测限可达2 mg/kg,花蛤样品最低检测限可达1 mg/kg。利用高效液相色谱法验证试纸条检测甲霜灵残留,主要数据验证结果一致。基于单克隆抗体的胶体金免疫条快速、灵敏、特异性强,适合作为水产品组织中甲霜灵残留检测的初筛方法。

Detection of metalaxyl residues in aquatic product based on monoclonal antibody-based colloidal gold test strips

To establish a rapid method for the determination of metalaxyl residues in aquatic products. In this paper, the metalaxyl colloidal gold immunochromatographic test strip was based on the immunological method of monoclonal antibody, the colloidal gold labeled metalaxyl ,monoclonal antibody was used as gold pad, metalaxyl-bovine serum albumin conjugate and goat anti-mouse IgG as detection line and quality control line. The results showed that the monoclonal antibody of metalaxyl was IgG1, Kappa type; heavy chain 50kD, light chain 20kD, molecular weight of about 150kD; affinity constant was 2.46×10⁹L/mol; IC50 was 59.57 ng/mL. The test strip can still be detected when the concentration of metalaxyl is 5mg/mL, and there was no cross-reactivity in the enrofloxacin, sulfamethoxazole, florfenicol, furazolidone, praziquantel, doxycycline, malachite green, methylene blue. The test strips were used to test the aquatic products such as Ctenopharyngodon idellus, Ruditapes philippinarum and Penaeus vannamei. The minimum detection limit of ctenopharyngodon idellus and Penaeus vannamei samples were 2mg/kg. The minimum detection limit of the Ruditapes philippinarum sample was up to 1mg/kg. The test strips were verified by high performance liquid chromatography to detect the residues of metalaxyl, and the results were consistent. Conclusion: The monoclonal antibody-based colloidal gold immunological strip is rapid, sensitive and specific, and is suitable for the detection of the primary screening method for the detection of metalaxyl residues in aquatic products.