SBIR-STTR Award

Food safety remains a critical issue for human health in our society. The food system in our nation is vulnerable to contamination from natural pathogens and from bio-terrorist attack. Current detection methods are inadequate due to the time-consuming and laboratory-centered approaches presently in use. Instruments for rapid on-site detection of pathogens in food are urgently needed. The objective of this project is to evaluate an innovative capillary bioseparator / bioreactor-based optical biosensor technology for rapid detection of E. coli O157:H7. The detection limit, specificity and detection time possible with this approach will be evaluated. It is expected that the technology will provide <100 cells/ml detection limit, <1 h detection time, and high specificity to E. coli O157:H7 (<1% false positive/negative data). Although the initial work will focus on food safety, similar technology can be utilized for rapid, on-site screening of human E. coli infections. Rapid screening of human infections is also very important because life-threatening E. coli infections are increasing especially in susceptible groups such as premature babies. Preliminary data indicate that the proposed approach has good potential to significantly improve the state-of-the-art in rapid, sensitive, and specific detection of E. coli O157:H7 and eventually other biological pathogens

The primary objective of this Phase II project is to develop an innovative benchtop instrument for use on-site at food processing facilities with high performance, ease-of-use, and a low per sample cost for rapid, specific, and sensitive detection of multiple pathogens including Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella Typhimurium in ready-to-eat (RTE) foods, such as processed meat and poultry products and fresh fruits and vegetables. Our proposed technique provides the ability to quantify pathogenic bacteria down to less than 10 cells/mL in less than one hour with a minimum of false positives or negatives. The proposed instrument is fully integrated and includes a cartridge containing multiple capillary column-based bioseparator/bioreactors (for pathogen capture), and a liquid core waveguide (LCW) optical detector (for pathogen detection). It will not require pre-enrichment of target bacteria in growth medium and all steps of the assay will require minimal operator skill. Microbial contamination of food products by pathogenic bacteria is a major concern of our society. Contaminated food is estimated to cause 76 million illnesses, 325,000 serious illnesses resulting in hospitalization, and 5,000 deaths in the United States each year. The economic impact of foodborne illness has been estimated as high as $10 billion annually. The Center for Science in the Public Interest reported that fruits and vegetables are the leading culprits in confirmed cases of foodborne illness in the United States. Of particular concern is the presence of pathogens in imported produce. Because of the persistence of these pathogens on fresh produce, both FDA and USDA have supported research on developing standardized methods to determine the efficacy of proposed sanitizer strategies for inactivating these pathogens on fresh produce. A heat kill step is not feasible for such foods. An obvious companion need in the U.S. food safety program is a rapid, simple method, such as is proposed here, to determine the number of pathogens that persist after the sanitizing step has been administered