Maintaining the expected quality and safety of food products is often difficult due to potential chemical and biological contamination. Of particular concern is the threat of food poisoning. Over 40 different foodborne microbial pathogens cause an estimated 30 million cases of human illness each year costing >$12 billion annually. Over the last 20 years, food-borne diseases caused by microbes have created increasingly significant concerns in the national political agenda and gained media attention. In addition to food-borne diseases, the use of pathogenic microorganisms as weapons of mass destruction remains a threat throughout the world. Agencies like, the United States Department of Agriculture (USDA) and the Department of Homeland Security must seek refined protocols for the rapid characterization and identification of pathogenic bacteria. Although, classical microbiological tests are available for detection and identification of pathogenic bacteria in samples, they usually involve a number of analytical steps of long duration and must be conducted by highly qualified scientific personnel. Therefore, new and faster techniques based on molecular biology principles have emerged during the last 10 years to supplement traditional methodology. This project will assess the feasibility to develop multi-layered nanoparticles that can be integrated into a Surface Enhanced Raman Spectroscopy (SERS) system for simple, accurate and sensitive detection of foodborne pathogens. Successful completion of this project will provide a new avenue for rapid bacterial detection along with a viable product to be developed for food safety markets. The advantageous characteristics of nanomaterials have made them an important component in a number emerging technologies. There are significant opportunities for the use of nano-material biosensors for food product and environmental monitoring, among many other offshoot applications. Therefore, development, of nanomaterial-based SERS biosensors has a high probability of usefulness. This Phase I grant is designed to build on preliminary research to prove the concept that SERS active nanoparticles can be designed and manufactured that can be directly used in a combinatorial approach to isolate and concentrate pathogenic microorganisms from food products as well as serve to enhance and develop a unique specific signal in a SERS optical biosensor. Both the particles and the optical method used to detect microorganisms have potential for commercialization.