The ability to stain live cells with a viability dye and preserve that staining pattern after fixation is critical for intracellular immunophenotyping. Exclusion of the dead cells from the data allows cleaner separation and identification of cell populations. The Invitrogen LIVE/DEAD Fixable Viability Dyes are fixable viability dyes that help ensure accurate assessment of cell viability in samples after fixation and/or permeabilization.

These flow cytometry–based kits offer you tools that are:

  • Flexible—14 different LIVE/DEAD dyes excited from UV, 405, 488, 532, 561, 633, or 808 nm lasers and emission choices to different channels
  • Robust—clear distinction of live and dead cells is preserved for up to 30 days after fixation
  • Simple—fit into almost any staining and immunophenotyping protocol
  • Exceptional choices—14 novel spectral signatures

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Fixable viability dyes for flow cytometry selection guide

LIVE/DEAD Fixable Dead Cell Stain kits are fixable viability dyes that distinguish live cells from dead cells based on cell membrane integrity and access to available amines. Cells can then be fixed for intracellular antigen detection without loss of original cell staining pattern. Allows easy exclusion of dead cells from flow cytometry readout. Dead cells are highly fluorescent and easy to distinguish from live cells, which are stained with minimal fluorescence.

All products come in three quantity options: 80, 200, 400 assays.

ProductLaser (nm)Ex/Em (nm)Dye compatibility
LIVE/DEAD Fixable Blue Dead Cell Stain KitUV350/450Cannot be used in combination with Invitrogen product line such as Indo-1 (blue), DAPI, or Hoechst 33342
LIVE/DEAD Fixable Violet Dead Cell Stain Kit405416/451Cannot be used in combination with Invitrogen product line such as Pacific Blue dye, CellTrace Violet stain, FxCycle Violet stain, BV421 or eFluor 450
LIVE/DEAD Fixable Lime (506) Viability Kit405405/506Cannot be used in combination with Invitrogen product line such as eFluor 506 and Pacific orange
LIVE/DEAD Fixable Aqua Dead Cell Stain Kit405367/526Cannot be used in combination with Invitrogen product line such as Pacific Green dye, F2N12S apoptosis assay, AmCyan, or BV510
LIVE/DEAD Fixable Yellow Dead Cell Stain Kit405400/575Cannot be used in combination with Invitrogen product line such as Pacific Orange dye, Qdot 605, F2N12S apoptosis assay, or BV605
LIVE/DEAD Fixable Green Dead Cell Stain Kit488495/520Cannot be used with NB510, NB530, NB555
LIVE/DEAD Fixable Olive (557) Viability Kit488480/557Can be used with NB510, FITC, AF488. Cannot be used with NB555, NB585
LIVE/DEAD Fixable Orange (602) Viability Kit561580/602Can be used with NB610. Cannot be used with NY590, NY610
LIVE/DEAD Fixable Red Dead Cell Stain Kit488/561595/615Cannot be used with NY610, NY590
LIVE/DEAD Fixable Far Red Dead Cell Stain Kit633/635650/665Cannot be used with NR660
LIVE/DEAD Fixable Scarlet (723) Viability Kit633/635702/723Cannot be used in combination with Invitrogen product line such as Alexa Fluor 700, APC-Cyanine 5.5, NovaFluor Red 700, and DRAQ5
LIVE/DEAD Fixable Near-IR Dead Cell Stain Kit633/635750/775Cannot be used in combination with Invitrogen product line such as APC-Alexa Fluor 750, APC-Cy 7 or Vybrant DyeCycle Ruby stain
LIVE/DEAD Fixable Near-IR (780) Viability Kit633/780633/785Cannot be used in combination with Invitrogen product line such as APC-Alexa Fluor 750, APC-eFluor 780
LIVE/DEAD Fixable Near-IR (876) Viability Kit808840/876NA
Not sure which dye will suit your needs? Try the LIVE/DEAD Fixable Dead Cell Stain Sampler Kit
Need compensation bead to use with LIVE/Dead stain kits? Use ArC Amine Reactive Compensation Bead Kit

LIVE/DEAD fixable technology

LIVE/DEAD Fixable Viability Stain Kits are based on the reaction of a fluorescent reactive dye with cellular proteins (amines). These dyes cannot penetrate live cell membranes, so only cell surface proteins are available to react with the dye, resulting in dim staining (Figure 1, LIVE). The reactive dye can permeate the damaged membranes of dead cells and stain both the interior and exterior amines, resulting in more intense staining (Figure 1, DEAD).

Graphic showing principle of LIVE/DEAD fixable viability stains
Figure 1. Principle of the LIVE/DEAD Fixable Viability Dead Cell Stains. The cell-impermeant, amine-reactive dye only binds to the surface of the live cell, resulting in very dim fluorescence. The dye can penetrate the cell membrane in dead cells and will bind to internal proteins, resulting in very bright fluorescence.

The difference in fluorescence intensity between the live and dead cell populations is typically greater than 50-fold, thereby allowing complete, simultaneous discrimination between the two cell populations (Figure 2A). Additionally, the covalent attachment of the dyes to proteins allows preservation of discrimination of the live and dead cell populations following fixation with formaldehyde, commonly used for intracellular immunophenotyping and to inactivate pathogens (Figure 2B). In contrast, non-fixable dyes including propidium iodide (PI) (Figure 3) lose staining pattern after fixation (Figure 3B).

Flow cytometry histograms showing distinct live and dead populations
Figure 2. Retention of LIVE/DEAD Fixable Viability Stains after fixation. The LIVE/DEAD Fixable Red Viability kit for 488 and 561 nm excitation was used to differentially stain a mixture of live (left peak) and heat-treated Jurkat cells (right peak). Cells in (A) were not fixed; cells in (B) were fixed in 3.7% formaldehyde following staining. Samples were analyzed by flow cytometry using 488 nm excitation and ~615 nm emission.
Flow cytometry histograms of cell count vs RFU before and after fixation

Figure 3. Cells stained with PI do not retain staining pattern after fixation. Propidium iodide (PI) was used to differentially stain a mixture of live (left peak) and heat-treated Jurkat cells (right peak). Cells in (A) were not fixed; cells in (B) were fixed in 3.7% formaldehyde following staining. Samples were analyzed by flow cytometry using 488 nm excitation and ~617 nm emission.

Protocol: LIVE/DEAD Fixable Dead Cell Stains

Article: Dead Cell Identification in Flow Cytometry


On demand webinar

Fixable viability dyes and applications for flow cytometry

This webinar gives an overview of methods and reagents to assess cell viability with flow cytometry. Discussion will focus on our most recent efforts to expand the color palette of fixable viability dyes. 



Additional resources

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Cy™ is a trademark or registered trademark of GE Healthcare.

Not for resale. Super Bright Polymer Dyes are sold under license from Becton, Dickinson and Company.

Brilliant Ultra Violet™ and Brilliant Violet™ are trademarks or registered trademarks of Becton, Dickinson and Company or its affiliates, and are used under license.

For Research Use Only. Not for use in diagnostic procedures.

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