An official website of the United States government.
The goal is to improve the detection of foodborne contaminants from pre-harvest through consumption of food products, thus meeting the USDA/NIFA goal to reduce foodborne illness and death through a safe food supply and to improve food safety for all Americans. <P> The project seeks to develop statistically valid sampling plans and detection methods for STEC and Salmonella. The supporting objectives are: 1) to design and develop an optical microplate array method for the simultaneous detection of multiple pathogens, including STEC, and Salmonella spp. using DNA sequence sandwich hybridization with oligonucleotide-functionalized Au nanoparticles (AuNPs), and 2) to develop a better estimation of the true level of contamination of STEC and Salmonella in beef and poultry products by employing a statistically valid, more robust, larger volume sampling plan.
NON-TECHNICAL SUMMARY: <BR> Foodborne illness continues to be a concern for the consumer, federal government, and industry. Development and adoption of detection technologies for foodborne pathogens, which are sensitive, specific, rapid, economical, and easily implemented is one of the important strategies to reduce the incidence of foodborne illness to the greatest extent. The goal of this project is to improve the detection of foodborne contaminants from pre-harvest through consumption of food products, thus meeting USDA/NIFA goal to reduce foodborne illness and death through a safe food supply and to improve food safety for all Americans. This project is expected to develop a novel, rapid, easily conducted, sensitive, and specific detection protocol for STEC and Salmonella from pre-harvest through consumption of food products.
<P> APPROACH:<BR> 1) We are going to develop an optical microplate array which is a label-free colorimetric method and can simultaneously and visibly detect multiple pathogens (STEC and Salmonella) by a color change through controlling DNA hybridization condition. When targets are hybridized with complementary AuNP-probes, the solution retained the initial red color. For non-targets, the phenomenon induces a color change from red to gray-blue following an increase in salt concentration and then quick cooling of the reaction solution, thus providing the basis of a direct colorimetric detection of the target DNA in the samples. The optical array loaded with species-specific AuNP- oilgonucleotide probes will be first tested in the mixture of pure culture setting and then applied in the environment samples (manure, soil, and water), group beef, and poultry products. 2) For the study of environmental, non-intact beef, and poultry samples, we will incorporate a sample pooling plan with an immunomagnetic separation/enrichment system for assessing the prevalence of STEC and Salmonella by the optical AuNPs microplate arrays.