Enrichment and detection of Escherichia coli O157:H7 from water samples using an antibody modified microfluidic chip. Academic Article uri icon

abstract

  • Low abundant (<100 cells mL(-1)) E. coli O157:H7 cells were isolated and enriched from environmental water samples using a microfluidic chip. The poly(methylmethacrylate), PMMA, chip contained 8 devices, each equipped with 16 curvilinear high aspect ratio channels that were covalently decorated with polyclonal anti-O157 antibodies (pAb) and could search for rare cells through a pAb mediated process. The chip could process independently 8 different samples or one sample using 8 different parallel inputs to increase volume processing throughput. After cell enrichment, cells were released and enumerated using benchtop real-time quantitative polymerase chain reaction (PCR), targeting genes which effectively discriminated the O157:H7 serotype from other nonpathogenic bacteria. The recovery of target cells from water samples was determined to be approximately 72%, and the limit-of-detection was found to be 6 colony forming units (cfu) using the slt1 gene as a reporter. We subsequently performed analysis of lake and wastewater samples. The simplicity in manufacturing and ease of operation makes this device attractive for the selection of pathogenic species from a variety of water supplies suspected of containing bacterial pathogens at extremely low frequencies.

published proceedings

  • Anal Chem

author list (cited authors)

  • Dharmasiri, U., Witek, M. A., Adams, A. A., Osiri, J. K., Hupert, M. L., Bianchi, T. S., Roelke, D. L., & Soper, S. A.

citation count

  • 87

complete list of authors

  • Dharmasiri, Udara||Witek, MaƂgorzata A||Adams, Andre A||Osiri, John K||Hupert, Mateusz L||Bianchi, Thomas S||Roelke, Daniel L||Soper, Steven A

publication date

  • April 2010