Microbial Contamination: Detection and Identification

C. Lloyd, H.-Y. Mason, Cory R. Estes, Andrew Duncan, Brad D. Wade, Walter R. Ellis, Jr., and Linda Powers

National Center for the Design of Molecular Function, Utah State University, Logan, UT 84322-4155, U.S.A.

e-mail: lsp@biocat.ncdmf.usu.edu

URL: http://www.engineering.usu.edu/Departments/

Recent deaths from microbial contamination in food and water, the recent terrorism of anthrax spores in mail, and the re-emergence of such diseases as tuberculosis have emphasized the importance of quick and accurate assessments of microbial contamination. Using a combination of unique technologies, microbe capture chips and a hand-held prototype detector have been developed which are capable of statistically sampling the environment for pathogens [including spores] and exotoxins, identifying the specific pathogens/exotoxins, and determining cell viability. This system can detect very low levels [~20 cells/cm2 on surfaces or ~100 cells/50 mL solution] of infectious bacteria in minutes. Microbe capture technology is based on molecular recognition and pathogenesis using iron acquisition, eukaryotic receptor adhesion strategies, and ligand binding to outer membrane and coat proteins. These non-antibody-based ligands are tethered to the sensor chip in a patterned array. Capture events are detected using intrinsic fluorescence of the cells and spores such as that from metabolites, amino acids, and other specific cell components.