Synchronous Quantitative Detection Of Escherichia Coli O157:H7and Shigella Boydii Based Visualization Antibody Macroarray Technology

With the national "Pathogenic Bacteria In Food Limited" standard promulgating,detection of foodborne pathogens will change from zero detection to limited detect in freshfood material, which made a new requirement to the current rapid detection field, currentnational standard quantitative detection methods are plate count, time-consuming relatively,this study aims to explore a rapid quantitative detection method based high-throughput proteinmicroarray, which provide a new ideas for the detection of foodborne pathogens.This study is based the principles of immunology "double antibody sandwich" method,based on a visual antibody macroarray technology for rapid synchronous quantitativedetecting Escherichia coli O157:H7and Shigella boydii.Use nitrocellulose membrane as substrate, whole experiment were all finish on thissubstrate. The target bacteria-specific antibodies were sprayed spot to substrate whichconstitute antibody macroarray, for detecting target bacteria in samples, then added to anotherspecific labeled antibody, and finally determine the results by chemical chromogenic method.Following made a imaging, analyzed gray value of each spot, made standard curve, got thenumber of pathogenic bacteria in the sample.The results show that visual antibody macroarray have good specificity to identifyEscherichia coli O157:H7and Shigella boydii, two bacterial detection sensitivity werereached3.4×105CFU/mL and3.2×105CFU/mL respectively, the corresponding standardcurve fitting is ideal, the trend of three standard curves is very similar to a parallel experiment,the coefficient of variation of the coordinate results is small enough to fully descriptionstability and reproducibility of the standard curve. The simulation of bacteria growth resultsshow, the majority results of standard curve calculate and plate count were in a same order ofmagnitudes except few results, which demonstrated feasibility of this study. Afterconventional ELISA and PCR methods were compared, there were same sensitivity for thethree methods, but this research only half or less time consuming compared to the two latter,and can realize the quantitative detection which has made some progress in rapid detection of food borne pathogenic.