UNIT 9.6 Estimation of Membrane Potential by Flow Cytometry

  1. Howard M. Shapiro

Published Online: 1 MAY 2004

DOI: 10.1002/0471142956.cy0906s28

Current Protocols in Cytometry

Current Protocols in Cytometry

How to Cite

Shapiro, H. M. 2004. Estimation of Membrane Potential by Flow Cytometry. Current Protocols in Cytometry. 28:9.6:9.6.1–9.6.12.

Author Information

  1. Howard M. Shapiro, M.D., P.C., West Newton, Massachusetts

Publication History

  1. Published Online: 1 MAY 2004
  2. Published Print: APR 2004


In most living cells, differences between interior and exterior concentrations of ions (e.g., Na+, K+, Cl-) generate an electrical potential across the cytoplasmic membrane. Membrane potential, like other cellular parameters, may change early in the course of surface receptor-mediated cell activation processes related to the development, differentiated function, and pathology of a large number of cell types. Changes in ionic environment may play a role in transmembrane signaling in response to cell surface ligand-receptor interactions. Thus, it is frequently of scientific interest to estimate membrane potential in individual cells. This unit provides methods for accomplishing this goal by flow or static cytometry using any of a number of cationic or anionic lipophilic fluorescent probes known as distributional dyes. The first of the two protocols is able to estimate the membrane potential of eukaryotic or bacterial cells. The second is more accurate, but can only be used with bacteria.


  • membrane potential;
  • ionic environment;
  • ligand-receptor interactions;
  • fluorescent lipophilic dyes;
  • mitochondrial membrane potential