Monitoring of Escherichia coli O157:H7 in food samples using lectin based surface plasmon resonance biosensor

A novel surface plasmon resonance (SPR) biosensor using lectin as bioreceptor was developed for the rapid detection of Escherichia coli (E. coli) O157:H7. The selective interaction of lectins with carbohydrate components from bacterial cells surface was used as the recognition principle for the detection. Five types of lectins from Triticum vulgaris, Canavailia ensiformis, Ulex europaeus, Arachis hypogaea, and Maackia amurensis, were employed to evaluate the selectivity of the approach for binding E. coli O157:H7 effectively. A detection limit of 3 × 103 cfu mL−1 was obtained for determination of E. coli O157:H7 when used the lectin from T. vulgaris as the binding molecule. Furthermore, the proposed biosensor was used to detect E. coli O157:H7 in real food samples. Results showed that the lectin based SPR biosensor was sensitive, reliable and effective for detection of E. coli O157:H7, which hold a great promise in food safety analysis.