为建立一种运用可视芯片技术快速、准确检测食品中肠出血性大肠埃希菌Escherichia coli O157:H7、志贺菌Shigella、沙门菌Salmonella、单核细胞增生李斯特菌Listeria monocytogenes的方法.分别选取肠出血性大肠埃希菌O157:H7中编码脂多糖O157抗原的基因(rfbE)、沙门菌中编码侵袭蛋白的基因(invA)、志贺菌中编码侵袭性质粒抗原H基因(ipaH)、单核细胞增生李斯特菌中编码PrfA蛋白基因(PrfA)设计引物和探针,探针5'标记一段polyT,下游引物5'端标记生物素,进行PCR扩增,将扩增产物与固定于可视芯片的特异性探针进行杂交分析.在均一的杂交条件下,能一一检测肠出血性大肠埃希菌O157:H7、志贺菌、沙门菌、单核细胞增生李斯特菌；以志贺菌为对象,该方法的检测灵敏度可达到670 cfu/mL.可以准确而稳定地实现对4种常见产毒微生物的通用检测.%In order to develop a rapid and accurate assay, based on the thin-film biosensor chips for the detection and identification of Escherichia. Coli O157: H7, Shigella, Salmonella, Listeria monocytogenes in food. rfbE (lipopolysaccharide O157 of S. E. coli) ,invA( invasion protein of S. Salmonella) , ipaH( invasion-associated plasmid antigen H of S. Shigella) and PrfA (PrfA protein of S. L monocytogenes) were used as target genes to design primers and probes. Thus,all the olignucleotide probes were labeled with 5' polyT group whereas the reverse primers were labeled with biotin. The genes were amplified and hybridized with probes on chip surface. Under the same condition,the detected "targe"pathogens were E. coli O157: H7, Shigella, Salmonella, L. monocytogene. Detection sensitivity of this system was upto 670 cfu/mL for Shigella. This method can be used rapidly and accurately to detect four species foodborne toxigenic mi-crobial.
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