Microplate Assays for Cell Viability

Microplate assays provide information on entire cell populations rather than tracking the behavior of individual cells. This high-throughput screening analysis can provide information for whole cells, disrupted cells, or cell lysates.

Microplate assays use various cellular functions to determine viability. Metabolic activity is commonly used as a viability indicator using the reducing power of living cells (alamarBlue and PrestoBlue) or cellular redox potential (MTT and XTT). For some applications, it can be important to assess viability independent of metabolic state, such as through the release of enzymatic proteins (CyQUANT Cytotoxicity assays) or loss of membrane integrity (LIVE/DEAD kits).

Microplate assays for cell viability selection guide

The alamarBlue and PrestoBlue Cell Viability Reagents are ready-to-use resazurin-based solution that function as a cell health indicator by using the reducing power of living cells to quantitatively measure viability.

	alamarBlue Cell Viability Reagent	alamarBlue HS Cell Viability Reagent	PrestoBlue Cell Viability Reagent	PrestoBlue HS Cell Viability Reagent
Assay type	Fluorescent
Use	Recommended in cases of extended viability studies or when using a high cell density in microplate assays		Recommended for quick viability determination in microplate assays (10-minute incubation)
Measurement	Detecting metabolic activity of mammalian cells, bacteria, plant, and fungi Only live cells detected		Detecting metabolic activity of mammalian cells Only live cells detected
Mechanism of detection	Resazurin is converted to fluorescent resorufin
Assay sensitivity
Cat. No.	DAL1025	A50100	A13261	P50200
	Learn more about differences in alamarBlue and alamarBlue HS		Learn more about differences in PrestoBlue and PrestoBlue HS

CyQUANT MTT and CyQUANT XTT Cell Viability Assays are reagents that function as a cell health indicator by using the cellular redox potential of live cells to quantitively measure cell viability and proliferation.

	CyQUANT MTT Cell Viability Assay	CyQUANT XTT Cell Viability Assay
Assay type	Colorimetric
Use	Well-established, end-point assay for quantitatively determining viability and proliferation	Quick and continuous assay for quantitatively determining viability and proliferation
Measurement	Detecting metabolic activity using the redox potential in active, live mammalian cells only
Mechanism of detection	Water-soluble MTT is converted into an insoluble purple formazan product	Water-soluble XTT is converted into a water-soluble orange formazan product
Kit components	MTT reagent (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) Sodium Dodecyl Sulfate (SDS)	XTT Reagent (2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide) Electron Coupling Reagent
Assay sensitivity
Cat. No.	V13154	X12223
	Learn more about differences in CyQUANT XTT and MTT Assays for Cell Viability

CyQUANT Cytotoxicity Assays use colorimetric- or fluorescent-based detection to measure the release of cytosolic enzymes, LDH or G6PD, from damaged cells.

	CyQUANT LDH Cytotoxicity Assay	CyQUANT LDH Cytotoxicity Assay- Fluorescence	CyQUANT Cytotoxicity Assay Kit (G6PD Release Assay)
Assay Type	Colorimetric	Fluorescent
Use	Multiplex with additional cell health assays Quantitate lactate dehydrogenase (LDH) release from damaged cells		Detection of low cell numbers Quantitate number of dead cells
Measurement	Detection of extracellular LDH from damaged cells Only damaged cells detected		Detection of the cytosolic enzyme glucose-6-phosphate dehydrogenase (G6PD) from damaged cells Only damaged cells detected
Mechanism of detection	Tetrazolium salt (INT) is converted to a red formazan	Resazurin is converted to a red fluorescent resorufin
Cat. No.	C20300	C20302	V23111
	Learn more about the differences in CyQUANT Cytotoxicity Assays

LIVE/DEAD kits can be used on microplate readers to discriminate live from dead cells through the influx of fluorescent dyes.

	LIVE/DEAD Viability/Cytotoxicity Kit, for mammalian cells	HCS LIVE/DEAD Green Kit
Assay type	Two-color, fluorescent assay
Use	Detection of live and dead cells	Detection of all cells and dead cells
Measurement	Influx of cell-impermeant dye in dead cells that have lost plasma membrane integrity Influx of cell-permeant dye in live cells that reacts with intracellular esterases	Influx of cell-impermeant dye in dead cells that have lost plasma membrane integrity Influx of cell-permeant dye(s) for total cell demarcation
Detection reagent (Ex./Em.)	Ethidium homodimer-1 (528/617 nm) Calcium AM (488/535 nm)	Image-iT DEAD Green (488/515 nm) NuclearMask Deep Red* (636/686 nm) Hoechst 33342* (350/461 nm) *For total cell demarcation, choose from one of these. Both are provided in the kit.
Cat. No.	L3224	H10290
	Learn more about LIVE/DEAD Cell Viability Assays

LIVE/DEAD kits can be used on microplate readers to detect bacterial or yeast viability through the influx of fluorescent dyes.

	LIVE/DEAD BacLight Bacterial Viability Kit	LIVE/DEAD Yeast Viability Kit
Assay type	Two-color fluorescent bacterial cell viability assay	Two-color fluorescent yeast cell viability assay
Measurement	Influx of cell-impermeant dye in cells that have lost plasma membrane integrity
Readout	Membrane-permeant DNA dye stains intact, live cells green Membrane-impermeant DNA stains dead cells red Live cell determination can also be combined with fluorescent Gram staining	A membrane stain detects both live and dead cells with a blue signal In viable cells, the vacuole stains orange/red
Detection reagent (Ex./Em.)	Propidium iodide (485/530 nm) SYTO 9 (630 nm)	FUN 1 (485/530 nm) Calcofluor White M2R (620 nm)
Cat. No.	L7012	L7009
	Learn more about LIVE/DEAD Cell Viability Assays

alamarBlue and
PrestoBlue reagents

	alamarBlue Cell Viability Reagent	alamarBlue HS Cell Viability Reagent	PrestoBlue Cell Viability Reagent	PrestoBlue HS Cell Viability Reagent
Assay type	Fluorescent
Use	Recommended in cases of extended viability studies or when using a high cell density in microplate assays		Recommended for quick viability determination in microplate assays (10-minute incubation)
Measurement	Detecting metabolic activity of mammalian cells, bacteria, plant, and fungi Only live cells detected		Detecting metabolic activity of mammalian cells Only live cells detected
Mechanism of detection	Resazurin is converted to fluorescent resorufin
Assay sensitivity
Cat. No.	DAL1025	A50100	A13261	P50200
	Learn more about differences in alamarBlue and alamarBlue HS		Learn more about differences in PrestoBlue and PrestoBlue HS

MTT and XTT
viability assays

	CyQUANT MTT Cell Viability Assay	CyQUANT XTT Cell Viability Assay
Assay type	Colorimetric
Use	Well-established, end-point assay for quantitatively determining viability and proliferation	Quick and continuous assay for quantitatively determining viability and proliferation
Measurement	Detecting metabolic activity using the redox potential in active, live mammalian cells only
Mechanism of detection	Water-soluble MTT is converted into an insoluble purple formazan product	Water-soluble XTT is converted into a water-soluble orange formazan product
Kit components	MTT reagent (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) Sodium Dodecyl Sulfate (SDS)	XTT Reagent (2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide) Electron Coupling Reagent
Assay sensitivity
Cat. No.	V13154	X12223
	Learn more about differences in CyQUANT XTT and MTT Assays for Cell Viability

LDH and G6PD
cytotoxicity assays

CyQUANT Cytotoxicity Assays use colorimetric- or fluorescent-based detection to measure the release of cytosolic enzymes, LDH or G6PD, from damaged cells.

	CyQUANT LDH Cytotoxicity Assay	CyQUANT LDH Cytotoxicity Assay- Fluorescence	CyQUANT Cytotoxicity Assay Kit (G6PD Release Assay)
Assay Type	Colorimetric	Fluorescent
Use	Multiplex with additional cell health assays Quantitate lactate dehydrogenase (LDH) release from damaged cells		Detection of low cell numbers Quantitate number of dead cells
Measurement	Detection of extracellular LDH from damaged cells Only damaged cells detected		Detection of the cytosolic enzyme glucose-6-phosphate dehydrogenase (G6PD) from damaged cells Only damaged cells detected
Mechanism of detection	Tetrazolium salt (INT) is converted to a red formazan	Resazurin is converted to a red fluorescent resorufin
Cat. No.	C20300	C20302	V23111
	Learn more about the differences in CyQUANT Cytotoxicity Assays

Membrane
integrity kits

LIVE/DEAD kits can be used on microplate readers to discriminate live from dead cells through the influx of fluorescent dyes.

	LIVE/DEAD Viability/Cytotoxicity Kit, for mammalian cells	HCS LIVE/DEAD Green Kit
Assay type	Two-color, fluorescent assay
Use	Detection of live and dead cells	Detection of all cells and dead cells
Measurement	Influx of cell-impermeant dye in dead cells that have lost plasma membrane integrity Influx of cell-permeant dye in live cells that reacts with intracellular esterases	Influx of cell-impermeant dye in dead cells that have lost plasma membrane integrity Influx of cell-permeant dye(s) for total cell demarcation
Detection reagent (Ex./Em.)	Ethidium homodimer-1 (528/617 nm) Calcium AM (488/535 nm)	Image-iT DEAD Green (488/515 nm) NuclearMask Deep Red* (636/686 nm) Hoechst 33342* (350/461 nm) *For total cell demarcation, choose from one of these. Both are provided in the kit.
Cat. No.	L3224	H10290
	Learn more about LIVE/DEAD Cell Viability Assays

Microorganism
kits

LIVE/DEAD kits can be used on microplate readers to detect bacterial or yeast viability through the influx of fluorescent dyes.

	LIVE/DEAD BacLight Bacterial Viability Kit	LIVE/DEAD Yeast Viability Kit
Assay type	Two-color fluorescent bacterial cell viability assay	Two-color fluorescent yeast cell viability assay
Measurement	Influx of cell-impermeant dye in cells that have lost plasma membrane integrity
Readout	Membrane-permeant DNA dye stains intact, live cells green Membrane-impermeant DNA stains dead cells red Live cell determination can also be combined with fluorescent Gram staining	A membrane stain detects both live and dead cells with a blue signal In viable cells, the vacuole stains orange/red
Detection reagent (Ex./Em.)	Propidium iodide (485/530 nm) SYTO 9 (630 nm)	FUN 1 (485/530 nm) Calcofluor White M2R (620 nm)
Cat. No.	L7012	L7009
	Learn more about LIVE/DEAD Cell Viability Assays

Expertly detect fluorescence with Thermo Scientific plate readers

High-sensitivity fluorescence detection for 6-1,536 samples can be quickly performed on the Varioskan ALF or Varioskan LUX Multimode Microplate Reader using Invitrogen reagents for optimal detection. Take advantage of automatic dynamic range selection to get optimal gain settings for each individual well and automation capabilities for even higher throughput.

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Resources

Cell Analysis Learning Center—Find educational resources such as application notes, webinars, videos, articles, and more that cover the use of many of our reagents and kits for cell analysis.

Fluorescence SpectraViewer—Online tool for visualization of the excitation and emission of fluorescent reagents; allows for checking spectral compatibility for multiple fluorophores.

Support

Cell Analysis Support Center—Find technical information, tips and tricks, and answers to everyday problems.

5 Steps resources

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

Microplate assays for cell viability selection guide

See also:

Expertly detect fluorescence with Thermo Scientific plate readers

Resources

Application notes

BioProbes article

Poster

Support

5 Steps resources