RESUMO
The primary objective of this research is to examine the feasibility of using an innovative technique based on laser-induced fluorescence coupled with flow cytometry to detect pathogenic microorganisms in food or water in real time. Our initial application is the rapid detection of E. coli O157:H7 in ground beef. The research performed demonstrated conclusively that this approach is feasible, and that the technique has key advantages over current alternatives including: it is (1) able to totally examine a large volume of food or water in real time, (2) capable of detecting single microorganisms (alternative techniques require in excess of 10(4) microorganisms), (3) intrinsically automatic, and (4) sensitive only to the selected bacteria. We have demonstrated the feasibility of detecting individual E. coli bacteria with a breadboard system. The performance of this system allows for rapid detection of individual specific pathogenic microorganisms. Two of the most significant commercial applications of this technique are the detection of infectious microorganisms in contaminated food and water. Food-borne microbial pathogens account for approximately 7 million illnesses and 9,000 deaths in the U.S. annually, with an estimated economic loss of at least $6 billion [1]. In addition, this method has the potential for a broad range of other commercial applications, including the detection of small numbers of molecules, such as the ultrasensitive detection of explosives and groundwater contaminants.