Abstract:A visualized microarray for rapid detection of nucleic acid of three food-borne pathogenic bacteria was developed. Substrate and detection probes which were complementary to both ends of Salmonella invA, Staphylococcus aureus nuc and Shigella ipaH genes were designed, respectively. Specific target sequences of three genes were also designed. One end of the specific target sequence or genomic DNA was hybridized with the amination probe fixed on the slide, and the other end was complementary to the sulfhydrylation probe to form a complex. The detection probe was connected with colloidal gold, and the signal was amplified by silver staining for the detection of food-borne pathogenic bacteria. Through comparative analysis of hybridization silver staining with genomic DNA, PCR products and specific target sequences, all results were positive, which demonstrated that the method could directly use genomic DNA to detect food-borne microorganisms rapidly and efficiently. The detection limit of genomic DNA of three foodborne pathogenic bacteria was 1 pmol/L, and clear results could be observed by naked eyes in the concentration range of 1 mmol/L ~1 pmol/L. The results of hybridization between probe and genomic DNA indicated that visual microarray had good specificity for the detection of microorganisms. Therefore, this method can detect food-borne microorganisms quickly and easily, and has broad market prospects.
