An official website of the United States government.

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Simultaneous Detection of Multiple Foodborne Pathogens with a Single Antibody-Based Test

Investigators
Carter, John Mark
Institutions
USDA - Agricultural Research Service
Start date
2012
End date
2014
Objective
The objective of this cooperative research project is to develop a multiplex superparamagnetic fluorescent microbead immunochemical assay for foodborne pathogens in food. Specifically, the scope of this project includes simultaneous detection and identification of the seven most common strains of Shiga toxin-producing Escherichia coli (STEC) based on O antigen: O157, O26, O111, O103, O121, O45, and O145. It also includes Listeria monocytogenes serotypes 1/2a, 1/2b, and 4b; and Salmonella enterica serovar Typhimurium. Foods of interest include ground beef, liquid egg, milk, and leafy greens. Performance characteristics of the product require sensitivity of at least one infectious dose of live bacteria per serving of food.
More information
Approach: The overall design includes three components: (1) cultural enrichment, (2) sandwich ELISA format assay using monoclonal antibodies, and (3) a microbead array platform. The improvements to the cultural enrichment step will be accomplished using incremental adjustments of existing standard microbiological media and do not concern this Agreement. An enrichment step is necessary to provide sufficient sensitivity for an assay that must detect the presence of only a few organisms in a sample of several hundred grams of food. The sandwich ELISA format we will employ is commonly performed in microplate format, and is typical for microbead immunochemical assays developed for the Luminex platform. We will use monoclonal and polyclonal antibodies provided by SDIX. Each antigen assay will be deployed on a unique fluorescent labeled microbead set. Specificity and sensitivity will be confirmed using bacteria grown in culture broth. Validation will be performed by University of South Florida (USF) and FDA. For validation experiments pathogens will be spiked into foods, and the Lower Limit Of Detection will be determined for each organism, in the presence of other pathogens and typical background flora.
Funding Source
Agricultural Research Service
Project source
View this project
Project number
2030-32000-009-03N
Accession number
421440
Categories
Escherichia coli
Listeria
Commodities
Eggs