Abstract:To investigate the application of DNA aptamers on detection and identification of food-borne pathogens, the whole-bacteria SELEX method was used to select single-stranded(ss) DNA aptamers with high binding affinity and specificity to Shigella flexneri. After multiple rounds of selection and counter-selection, 17 supposed aptamers were obtained from the enriched pool. Among them, 4 high-frequency aptamers were found to have significant affinities and specificities to S. flexneri. Further analysis indicated that F-1 and F-9 displayed higher affinities, and their binding affinity to S. flexneri were (51.3 ± 3.25) nmol/L and (42.6 ± 7.11) nmol/L, respectively. According to the Mfold software, the minimum free energy (dG) of F-1 and F-9 were determined to be -7.39 and -6.98 kcal/mol, respectively. The present study demonstrated the feasibility to detect S. flexneri by aptamers, which would pave the way for its application in diagnosing food-borne pathogens.