Detection and Identification of Foodborne Toxigenic Microbial by Using Thin-Film Biosensor Chips

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 microbial.