UNIT 9.38 A Violet Ratiometric Membrane Probe for the Detection of Apoptosis

  1. William G. Telford

Published Online: 1 JAN 2012

DOI: 10.1002/0471142956.cy0938s59

Current Protocols in Cytometry

Current Protocols in Cytometry

How to Cite

Telford, W. G. 2012. A Violet Ratiometric Membrane Probe for the Detection of Apoptosis. Current Protocols in Cytometry. 59:9.38:9.38.1–9.38.12.

Author Information

  1. Experimental Transplantation and Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland

Publication History

  1. Published Online: 1 JAN 2012
  2. Published Print: JAN 2012


This unit describes the use of a novel violet-excited membrane-binding probe F2N12S [4′-N,N-diethylamino-6-(N,N,N-dodecyl-methylamino-sulfopropyl)-methyl-3-hydroxyflavone] for the flow cytometric detection of the changes in membrane asymmetry, fluidity, and charge that accompanies apoptosis. This reagent inserts into the plasma membrane and undergoes a shift in emission from orange to green during the membrane alterations that occur during apoptosis. Since its mechanism of action differs from annexin V, it can be used in situations where annexin V binding is problematic, as in adherent cells removed from their growth substrate. Like annexin V, it can also be readily combined with other flow cytometric assays for apoptosis, allowing detailed multiparametric analysis of the apoptotic process. Curr. Protoc. Cytom. 59:9.38.1-9.38.12. © 2012 by John Wiley & Sons, Inc.


  • apoptosis;
  • membrane probe;
  • annexin V;
  • F2N12S