定性测定羊奶中黄曲霉毒素M1残留的高灵敏度检测卡的研制

Development of detection card for the qualitative determination of aflatoxin M1 in ewe′s milk

为研制定性测定羊奶中黄曲霉毒素M1残留的高灵敏度检测卡,在硝酸纤维素膜上预包被黄曲霉毒素M1全抗原作为检测线,在硝酸纤维素膜上预包被羊抗鼠二抗作为质控线。将抗黄曲霉毒素M1单克隆抗体用胶体金标记作为金标垫。将样品垫、金标垫、预包被黄曲霉毒素M1的硝酸纤维素膜以及吸水垫依次粘贴在PVC板上,切割成4 mm宽的试纸条,将试纸条装入塑料卡壳中扣紧组装成检测卡。样本中残留的黄曲霉毒素M1与硝酸纤维素膜上的检测线共同竞争胶体金标记的黄曲霉毒素M1抗体,检测线的颜色深浅与其残留物黄曲霉毒素M1呈负相关,从而判定样品中黄曲霉毒素M1的含量。结果表明,检测卡的检测限为0.5μg/L,黄曲霉毒素M1检测卡对黄曲霉毒素M1的交叉反应率为100%,而与同族的其他物质的交叉反应率小于5%,与不同族的其他物质的交叉反应率小于1%。假阳性率小于5%,假阴性率为0%,密封好的检测卡常温下储存,保质期18个月。本研究为快速准确地测定羊奶中黄曲霉毒素M1残留提供了物质基础。

This study is aimed to develop a kind of sensitive detection card for the qualitative determination of aflatoxin M1 residues in milk.The aflatoxin M1 antigen precoated on nitrocellulose membrane was used as detection line,with goat anti-mouse antibody as control line.The anti-aflatoxin M1 monoclonal antibody was labeled on colloidal gold as gold labeled pad.The sample pad,gold labeled pad,nitrocellulose membrane and an absorbent pad were attached on the PVC board,and then PVC was cut into a 4-mm-wide strip.The strip was put into the plastic shell and thus detection card was developed.Aflatoxin M1 residues in samples and the precoated aflatoxin M1 antigen on nitrocellulose membrane competed the colloidal gold labeled aflatoxin M1 antibody.The depth of detection line was negatively associated with the content of aflatoxin M1 in samples.The results showed that the detection limit of detection card was 0.5μg/L,and the cross-reactivity rate with aflatoxin M1 was 100%,less than 5% with analogues,less than 1% with other substances.The false positive rate was less than 5%,the false negative rate was 0,and shelf life was 18 months at room temperature.Conclusion： This detection card provides material for qualitative detection of aflatoxin M1 residues in ewe′s milk.