Fluorescent DNA Aptamer Test Strips for more sensitive and rapid assessment of food safety.

Most commercially available antibody-based test strips for the detection of foodborne pathogenic bacteria are rapid (work in minutes), but not very sensitive. Operational Technologies Corporation (OpTech) aims to improve the sensitivity of such test strips by using higher affinity and more specific DNA aptamers in place of the antibodies. In addition, OpTech will couple its aptamer-based test strips to fluorescent nanoparticles (FNPs) or quantum dots (QDs) because these have been shown to increase the visual sensitivity of test strips about ten-fold when an ultraviolet penlight is used as the fluorescence excitation source. OpTech will develop as many test strip prototypes as it can in Phase 1 using its existing patent-pending (U.S. patent application no. 13/136,820)DNA aptamer library for foodborne pathogens and toxins. OpTech will also develop new aptamers against the so called "Big 6" non-O157 E. coli which are known to cause disease and are now mandated for testing by the USDA. Finally, OpTech will investigate the use of its new Big 6 E. coli aptamers in fluorescent test strips. The end result of this research and development effort should be more sensitive foodborne pathogen and biotoxin detection in the popular and portable test strip format using fluorescence detection, leading to a safer food supply.