Analytical and Bioanalytical Chemistry

, Volume 406, Issue 1, pp 183–192

Differentiation of Escherichia coli serotypes using DC gradient insulator dielectrophoresis

  • Paul V. Jones
  • Alexa F. DeMichele
  • LaKeta Kemp
  • Mark A. Hayes
Research Paper

DOI: 10.1007/s00216-013-7437-5

Cite this article as:
Jones, P.V., DeMichele, A.F., Kemp, L. et al. Anal Bioanal Chem (2014) 406: 183. doi:10.1007/s00216-013-7437-5

Abstract

Bacteria play a significant role in both human health and disease. An estimated 9.4 million cases of foodborne illness occur in the United States each year. As a result, rapid identification and characterization of microorganisms remains an important research objective. Despite limitations, selective culturing retains a central role among a cadre of identification strategies. For the past decade, separations-based approaches to rapid bacterial identification have been under investigation. Gradient insulator dielectrophoresis (g-iDEP) promises benefits in the form of rapid and specific separation of very similar bacteria, including serotypes of a single species. Furthermore, this approach allows simultaneous concentration of analyte, facilitating detection and downstream analysis. Differentiation of three serotypes or strains of Escherichia coli bacteria is demonstrated within a single g-iDEP microchannel, based on their characteristic electrokinetic properties. Whole cells were captured and concentrated using a range of applied potentials, which generated average electric fields between 160 and 470 V/cm. Bacteria remained viable after exposure to these fields, as determined by cellular motility. These results indicate the potential g-iDEP holds in terms of both separatory power and the possibility for diagnostic applications.

Keywords

Dielectrophoresis Escherichia coli Bioanalytical methods Electrokinetic separations Microfluidics 

Abbreviations

DC

Direct current

DEP

Dielectrophoresis

EOF

Electroosmotic flow

EP

Electrophoresis

g-iDEP

Gradient-insulator-based dielectrophoresis

iDEP

Insulator dielectrophoresis

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Paul V. Jones
    • 1
  • Alexa F. DeMichele
    • 1
  • LaKeta Kemp
    • 1
  • Mark A. Hayes
    • 1
  1. 1.Department of Chemistry and BiochemistryArizona State UniversityTempeUSA