UNIT 11.3 Estimation of Microbial Viability Using Flow Cytometry

  1. Hazel M. Davey1,
  2. Douglas B. Kell2,
  3. Dieter H. Weichart3,
  4. Arseny S. Kaprelyants4

Published Online: 1 SEP 2004

DOI: 10.1002/0471142956.cy1103s29

Current Protocols in Cytometry

Current Protocols in Cytometry

How to Cite

Davey, H. M., Kell, D. B., Weichart, D. H. and Kaprelyants, A. S. 2004. Estimation of Microbial Viability Using Flow Cytometry. Current Protocols in Cytometry. 29:11.3:11.3.1–11.3.21.

Author Information

  1. 1

    University of Wales, Aberystwyth, United Kingdom

  2. 2

    University of Manchester Institute of Science and Technology, Manchester, United Kingdom

  3. 3

    Max Planck Institut für Molekulare Genetik, Berlin, Germany

  4. 4

    Russian Academy of Sciences, Moscow, Russia

Publication History

  1. Published Online: 1 SEP 2004
  2. Published Print: JUL 2004


For microorganisms in particular, viability is a term that is difficult to define and a state consequently difficult to measure. The traditional (and gold-standard) usage equates viability and culturability (i.e., the ability to multiply), but the process of determining culturability is often too slow. Flow cytometry provides the opportunity to make rapid and quantitative measurements of dye uptake in large numbers of cells, and we can therefore exploit the flow cytometric approach to evaluate so-called viability stains and to develop protocols for more routine assessments of microbial viability. This unit is primarily commentary, but several basic protocols have been included to ensure that users have a firm basis for attempting these reasonably difficult assays on traditional flow cytometer instruments. What is clear is that each assay must be carefully validated with the particular microorganism of interest before being applied in any research, clinical, or service form.