Application of F0F1­ATPase immuno­biosensors for detecting Escherichia coli O157:H7.

Escherichia coli (E. coli) O157:H7 is an important food­borne pathogen with a low infective threshold and high resistance to treatment. There are currently a number of detection methods available, however, the majority are time­consuming, complex and expensive, thus it is hard for these methods to be applied in routine detection. Therefore, there is urgent requirement to develop more sensitive, rapid and specific detective techniques. In the present study, an immuno­biosensor based on the interference of load to the F0F1­ATPase rotation, indicated by the fluorescence fluctuation, was constructed to detect O157:H7. The results demonstrated a good linear relationship (R2=0.9818) between antigen concentration (range, 102 cfu to 104 cfu) and the fluorescence intensity. The detection signals of the samples containing 102 cfu/well and 104 cfu/well E. coli O157:H7 were significantly stronger than the signal produced by the control sample (P<0.01). Due to its higher sensibility and simplicity when compared with the current methods applied, the results of the present study indicate a promising future for the application of this technique in detecting food source pathogens.