LIVE/DEAD® Cell Viability Assays  

We offer complete solutions for easy, sensitive determination of cell viability, cell vitality, and compound cytotoxicity. These fluorescence-based Molecular Probes™ LIVE/DEAD™ assays can be used to examine animal cells, bacteria, yeast, and fungi. Specific LIVE/DEAD assays can be used for flow cytometry, microscopy, or microplate formats. Fluorescent dyes used in the viability assays range from blue to near-IR emission. Our LIVE/DEAD fixable viability assays permit fixation, which enables intracellular staining and neutralization of pathogens.

LIVE/DEAD Kits for mammalian cells

These kits combine fluorescent reagents to yield, in most cases, two-color discrimination of the population of live cells from the dead-cell population without any wash steps. These are ideal for high-throughput screening, imaging, fluorometry and flow cytometry.

LIVE/DEAD Kits for yeast and fungi

Our LIVE/DEAD Yeast Viability Kits provide an extremely simple and sensitive assay for discriminating viable yeast and fungi in complex mixtures or in pure cultures. The Yeast Viability Kit uses FUN 1 dye and Calcofluor White M2R. The FungaLight™ Yeast Viability Kit uses 2 nucleic acids stains.

LIVE/DEAD Kits for bacteria

The LIVE/DEAD BacLight™ Bacterial Viability Kits provide two different nucleic acid stains to rapidly distinguish live bacteria with intact plasma membranes from dead bacteria with compromised membranes.

LIVE/DEAD Fixable Stains for flow cytometry

LIVE/DEAD Fixable Dead Cell Stain Kits allow you to accurately distinguish live and dead cells when performing intracellular staining in flow cytometry. Additionally, the dyes in the kits react covalently with protein so that the discrimination is completely preserved following fixation of the sample by formaldehyde, under conditions that inactivate pathogens.

two flow cytometry histograms showing no change in the fluorescence intensity peaks detected in the unfixed and the fixed cell samples

Retention of LIVE/DEAD Fixable Dead Cell Stains after fixation. The LIVE/ DEAD Fixable Aqua Dead Cell Stain Kit 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 405 nm excitation and ~525 nm emission.

Selection guides for LIVE/DEADCell Viability Assay Kits

LIVE/DEAD Kits for mammalian cells

Kit Name Platform* Fluorescent Dyes Ex/Em (nm) Em Colors Cat. No.
LIVE/DEAD Viability/Cytotoxicity Kit for mammalian cells FC, FM, M calcein AM ethidium homodimer-1 494/517
517/617		 Green (Live)
Red (Dead)		 L3224
LIVE/DEAD Cell-Mediated Cytotoxicity Kit  for animal cells, 2000 assays FC, FM, M DiOC18(3)
propidium iodide		 484/501
536/617		 Green (Live)
Red (Dead)		 L7010
LIVE/DEAD Sperm Viability Kit 200–1,000 assays FC, FM SYBR™ 14 dye
propidium iodide		 485/517
536/617		 Green (Live)
Red (Dead)		 L7011
LIVE/DEAD Cell Vitality Assay Kit C12-resazurin/SYTOX™ Green 1,000 assays FC, FM, M SYTOX™ Green dye
C12-resazurin		 488/530
488/575		 Green (Dead)
Red (Live)		 L34951
*FC = flow cytometry; FM = fluorescence microscopy; M = microplate assay

LIVE/DEAD Cell Viability/Cytotoxicity Assay Kit. A mixture of live and ethanol-killed bovine pulmonary artery epithelial cells were stained with the reagents in our LIVE/DEAD Cell Viability/Cytotoxicity Assay Kit. Live  cells fluoresce bright green, whereas dead cells with compromised membranes fluoresce red-orange.
  
LIVE/DEAD Sperm Viability Kit. Live sperm with intact membranes are labeled with our proprietary cell-permeant nucleic acid stain, SYBR™ 14, and fluoresce green. Dead sperm, which have been killed by unprotected freeze-thawing, are labeled with propidium iodide and fluoresce red-orange. The image was contributed by Duane L. Garner, School of Veterinary Medicine, University of Nevada, Reno, and Lawrence A. Johnson, USDA Agricultural Research Service.

  LIVE/DEAD Cell Vitality Kit. Jurkat cells (T-cell leukemia, human) were induced with 10 μM camptothecin for 4 hours at 37°C, 5% CO2. The cells were incubated with the reagents in the LIVE/DEAD Cell Vitality Assay Kit and analyzed by flow cytometry. The dot plot of SYTOX Green fluorescence vs. resorufin fluorescence shows resolution of live, injured, and dead cell populations.

LIVE/DEAD Kits for Yeast and Fungi

Kit Name Platform* Fluorescent Dyes Ex/Em Em Colors Cat. No.
LIVE/DEAD Yeast Viability Kit FM, M FUN 1
Calcofluor White M2R

488/530 (all)
488/560-610 (Live)

365/440

Green (All)
Red-orange (Live)
Blue (All)

 L7009
LIVE/DEAD FungaLight™ Yeast Viability Kit FC SYTO™ 9 dye
propidium iodide		 485/530
485/630		 Green (Live)
Red (Dead)		 L34952
*FC = flow cytometry; FM = fluorescence microscopy; M = microplate assay

  LIVE/DEAD® Yeast Viability Kit. Saccharomyces cerevisiae stained with the FUN® 1 cell stain, which generates red-fluorescent intravacuolar structures, and with Calcofluor White M2R, a blue-fluorescent cell wall stain. Both probes are provided in our LIVE/DEAD® Yeast Viability Kit. FUN® 1 cell stain is also available separately.


Saccharomyces spp. cell suspensions stained with SYTO® 9 dye and propidium iodide and analyzed using a BD FACSCalibur™ flow cytometry system (Becton Dickinson and Co.). Panel A shows the dot plot of forward scatter vs. side scatter of an untreated Saccharomyces culture, washed and stained with SYTO® 9 dye and propidium iodide as described in the protocol. The region R1 contains particles of the appropriate size for yeast cells; the forward scatter trigger is set to exclude debris in the sample. Panel B shows the R1-gated staining pattern obtained following analysis of a sample of yeast containing a mixture of both live and heat-killed cells.

LIVE/DEAD Kits for bacteria

Kit Name Format Platform* Fluorescent Dyes Ex/Em (nm) Em Colors Cat. No.
LIVE/DEAD BacLight Bacterial Viability Kit Stains are supplied in a mixed, two-component formulation FC, FM, M SYTO 9 dye
propidium iodide		 485/530
485/630		 Green (Live)
Red (Dead)		 L7007
LIVE/DEAD BacLight Bacterial Viability Kit The stains are provided as separate solutions FC, FM, M SYTO 9 dye
propidium iodide		 485/530
485/630		 Green (Live)
Red (Dead)		 L7012
LIVE/DEAD BacLight Bacterial Viability Kit Separate dyes are dry and premeasured into pairs of polyethylene transfer pipets FC, FM, M SYTO 9 dye
propidium iodide		 485/530
485/630		 Green (Live)
Red (Dead)		 L13152
LIVE/DEAD BacLight Bacterial Viability and Counting Kit Microsphere standard is also included FC SYTO 9 dye
propidium iodide
 485/530
485/630		 Green (Live)
Red (Dead)
 L34856
*FC = flow cytometry; FM = fluorescence microscopy; M = microplate assay


Use our LIVE/DEAD BacLight™ Bacterial Viability Kit to identify individual live and dead bacteria along a chain of Streptococcus pyogenes. This image was photographed in a single exposure through an Omega Optical triple bandpass filter set.

  

Analysis of bacterial cultures using the LIVE/DEAD BacLight Bacterial Viability and Counting Kit. Suspensions of live (untreated) and dead (alcohol-treated) Staphylococcus aureus (Panels A and C) and Escherichia coli (Panels B and D) were stained and analyzed by flow cytometry according to the kit protocol. Using green or red fluorescence versus side scatter cytogram (Panels A and B), the bacterial populations and the bead populations were gated (left and right boxes, respectively). Events in the bacteria region of each cytogram are also displayed in red fluorescence versus green fluorescence cytograms (Panels C and D). Live and dead bacteria/mL can be calculated from either the fluorescence versus side scatter cytogram or the green fluorescence versus red fluorescence cytogram, depending on which one shows the best separation of the live and dead populations. The position of the live and dead populations in these cytograms may be dependent on cell type and gram character. Some samples may exhibit events that fall outside the defined regions and should be evaluated appropriately (e.g., see Panel D).

Resources