胶体金试纸条快速检测动物源性食品中头孢氨苄残留

A Gold Nanoparticle-based Immunochromatographic Assay for Rapid Determination of Cephalexin in Animal-derived Foods

头孢菌素类抗生素属于第二种类型的β-内酰胺类抗生素,其在动物源性食品中的残留问题引起普遍关注.为保障食品安全,实现对食品中头孢菌素类抗生素残留的快速检测,该研究利用金纳米颗粒标记头孢氨苄(cefalexin,CEX)兔多克隆抗体作为可视化信号探针,基于硝酸纤维素膜研制一种能够检测头孢菌素类抗生素的免疫层析检测试纸.试纸条以CEX包被原为检测线,以羊抗兔二抗为质控线,对试验条件进行优化后,所构建的试纸条在缓冲液体系中对CEX、头孢拉定(cefradine,RAD)和头孢羟氨苄(cefadroxil,CFR)的检测限分别可达到20、25、25μg/L.为验证方法的实用性,将一定浓度的CEX添加至虾肉、牛奶、牛肉、猪肉、生猪肝和熟猪肝6种常见的动物源性食品中进行添加回收测定.结果显示:经过简单的样品处理,所构建的试纸条在10 min内即可实现对目标物的快速可视化检测.该方法操作简便、快速,适用于大批量动物性食品中多种头孢菌素类残留的高通量筛查.

Cephalosporin antibiotics are the second type ofβ-lactam antibiotics.It is extremely easy for animal-derived food to be contaminated with cephalosporin antibiotics,resulting in an increasing public attention.In this study,a nitrocellulose membrane-based immunochromatographic test trip was constructed for multi-residues determination of 3 kinds of cephalosporin antibiotics.In this test strip,AuNPs modified anti-cephalexin rabbit polyclonal antibody was applied as the visual probe;the cephalexin antigen and the anti-rabbit goat antibody was used as the control line and the test line,respectively.Under the optimized experimental conditions,the detection limits of this test strip towards cephalexin,cephradine,and cefadroxil were 20,25,25μg/L,respectively.To verify the practicability of this developed test strip,we added a certain concentration of cephalexin in shrimp,milk,beef,pork,raw pig liver,and cooked pig liver sample for recovery test.The results showed that,after a sample pretreatment,the test strip provided the visual signals within 10 minutes.The established method in this study was simple and rapid,and was suitable for rapidly screening large numbers of animal-derived food samples.