胶体金免疫层析法快速检测动物源性食品中土霉素残留

Rapid detection of oxytetracycline residues in animal derived foods by colloidal gold immunochromatography

中文关键词:  土霉素  胶体金  试纸条  快速检测

英文关键词:oxytetracycline  colloidal gold  test strip  rapid detection

中文摘要:

      目的 建立用于快速检测动物源性食品中土霉素残留的胶体金免疫层析试纸条。方法 采用柠檬酸三钠还原法制备胶体金, 胶体金粒径选用20 nm, 将经鉴定制备成功的胶体金溶液与土霉素多克隆抗体结合得到金标抗体。优化金标抗体的制备条件, 将包被抗原(1.0 mg/mL)和羊抗鼠二抗(0.75 mg/mL)分别作为检测线和质控线包被在硝酸纤维素(nitrocellulose, NC)膜上, 金标抗体按一定浓度包被在玻璃纤维垫上, 对样品垫和吸收垫进行裁剪处理, 通过上述预处理将每部分依次叠加粘贴至底板, 制成胶体金试纸条。结果 土霉素胶体金试纸条在实际样品中的检出限为30 μg/L; 土霉素胶体金免疫层析试纸条与沙拉沙星、莱克多巴胺、氨苄青霉素、恩诺沙星(非本族兽药)无交叉反应。结论 该试纸条具有较强特异性、检测时间短、操作方便优点, 可作为土霉素残留现场检查的有效手段。

英文摘要:

      Objective To establish a colloidal gold immunochromatographic strip for rapid determination of oxytetracycline residues in animal derived foods. Methods Colloidal gold was prepared by trisodium citrate reduction method, the particle size of colloidal gold was 20 nm, the gold labeled antibody was obtained by combining the colloidal gold solution successfully prepared by identification with oxytetracycline polyclonal antibody. The preparation conditions of gold labeled antibody were optimized, the coating antigen (1.0 mg/mL) and sheep anti-mouse secondary antibody (0.75 mg/mL) were coated on the nitrocellulose (NC) membrane as the detection line and quality control line, respectively, the gold labeled antibody was coated on the glass fiber pad according to a certain concentration, the sample pad and absorption pad were cut and pasted to the bottom plate through the above pretreatment to make colloidal gold test strip. Results The limit of detection of oxytetracycline colloidal gold test strip in actual samples was 30 μg/L; there was no cross reaction between oxytetracycline colloidal gold immunochromatographic strip and sarafloxacin, ractopamine, ampicillin and enrofloxacin (non native veterinary drugs). Conclusion The test strip has the advantages of strong specificity, short detection time and convenient operation, it can be used as an effective means for on-site inspection of oxytetracycline residues.