基于上转发光免疫层析技术快速检测单核细胞增生李斯特菌

摘要

Objective To develop an up-converting phosphor technology-based lateral-flow ( UPT-LF) assay for rapid detection of Listeria monocytogenes, named LM -UPT-LF.Methods Monoclonal antibodies against p 60, which was the specific virulence factor of L.monocytogenes,were prepared and covalently conjugated with up-converting phosphor nanopar-ticles (UCP-NPs) as bio-label.Then, LM-UPT-LF was established with double-antibody sandwich mode-based LF assay. Detection performance , including sensitivity and specificity , was evaluated .Results The samples with absolute contamina-ted amount of L.monocytogenes cells <10, 10-99, and 100-1000 cfu could be significantly detected as positive after in-cubation at 20 h, 18 h, and 16 h, respectively.Other 13 kinds of food-borne pathogens with concentration of 109 cfu/ml did not caused any non-specific reaction .Conclusion The established LM-UPT-LF assay could detect L.monocytogenes with high sensitivity , specificity and simplicity and provides an alternative method for food safety control .%目的：建立可快速检测单核细胞增生李斯特菌（ Listeria monocytogenes， LM）的上转发光免疫层析技术（ up-converting phosphor technology based lateral flow assay ， UPT-LF），即LM-UPT-LF。方法针对LM特异的p60蛋白制备单克隆抗体，并与上转发光纳米颗粒（ up-converting phosphor nanoparticles ， UCP-NPs）共价偶联作为结合物，采用双抗体夹心免疫层析模式建立LM-UPT-LF，并对其敏感性与特异性进行评价。结果建立了可快速检测LM的LM-UPT-LF平台，在样本＜10 cfu、10～99 cfu、100～1000 cfu绝对LM污染量条件下可分别在培养20、18、16 h检出阳性。其他13种食源性致病菌在高浓度（109 cfu／ml）时无非特异性交叉。结论所建立的LM-UPT-LF操作简便快速，具有良好的敏感性和特异性，适用于一线病原调查与检测。