Antibody-aptamer functionalized fibre-optic biosensor for specific detection of Listeria monocytogenes from food

作者：Ohk S H; Koo O K; Sen T; Yamamoto C M; Bhunia A K^*

来源：Journal of Applied Microbiology, 2010, 109(3): 808-817.

DOI：10.1111/j.1365-2672.2010.04709.x

• aptamer
• detection
• fibre-optic sensor
• food
• Listeria monocytogenes

Aim:
To develop antibody-aptamer functionalized fibre-optic biosensor for specific detection of Listeria monocytogenes from food products.
Methods and Results:
Aptamer, a single-stranded oligonucleotide ligand that displays affinity for the target molecule, was used in the assay to provide sensor specificity. Aptamer-A8, specific for internalin A, an invasin protein of L. monocytogenes, was used in the fibre-optic sensor together with antibody in a sandwich format for detection of L. monocytogenes from food. Biotinylated polyclonal anti-Listeria antibody, P66, was immobilized on streptavidin-coated optical waveguide surface for capturing bacteria, and Alexa Fluor 647-conjugated A8 was used as a reporter. The biosensor was able to selectively detect pathogenic Listeria in pure culture and in mixture with other bacteria at a concentration of approx. 103 CFU ml-1. This sensor also successfully detected L. monocytogenes cells from artificially contaminated (initial inoculation of 102 CFU 25 g-1) ready-to-eat meat products such as sliced beef, chicken and turkey after 18 h of enrichment.
Conclusion:
Based on the data presented in this study, the antibody-aptamer functionalized fibre-optic biosensor could be used as a detection tool for sensitive and specific detection of L. monocytogenes from foods.
Significance and Impact of the Study:
The study demonstrates feasibility and novel application of aptamer on fibre-optic biosensor platform for the sensitive detection of L. monocytogenes from food products.

• 出版日期2010-9