Shop All Apoptosis Kits

Click-iT™ TUNEL Alexa Fluor™ 488 Imaging Assay, for microscopy & HCS (Invitrogen™)

The Click-iT® TUNEL Alexa Fluor® 488 Imaging Assay utilizes a dUTP modified with an alkyne, a small, bio-orthogonal functional group that enables the nucleotide to be more readily incorporated by TdT than other modified nucleotides, including BrdUTP, biotin-dUTP or fluorescein-dUTP. Detection is based on a click reaction, a copper (I) catalyzed reaction between an azide and alkyne. Click chemistry fills the void when methods such as direct labeling or the use of antibodies are not efficient. The small size of the detection reagent, an Alexa Fluor® azide (MW <~1000) compared to that of an antibody (MW ~150,000) enables facile penetration of complex samples with only mild fixation and permeabilization required.

Compared to other assays using one of the other modified nucleotides, the Click-iT® TUNEL assay is able to detect a higher percentage of apoptotic cells under identical conditions. The assay is also fast and is complete within 2 hours. Furthermore, the Click-iT® TUNEL assay allows multiplexing with surface and intracellular biomarker detection.

More tools for apoptosis detection and measurement >

eBioscience™ Annexin V-Biotin Apoptosis Detection Kit (Invitrogen™)

Annexins are a family of calcium-dependent phospholipid-binding proteins, which bind to phosphatidylserine (PS) to identify apoptotic cells. In healthy cells, PS is predominantly located along the cytosolic side of the plasma membrane. Upon initiation of apoptosis, PS loses its asymmetric distribution in the phospholipid bilayer and translocates to the extracellular membrane, which is detectable with fluorescently labeled Annexin V. In early stages of apoptosis, the plasma membrane excludes viability dyes such as propidium iodide (PI) and 7-AAD, therefore cells which display only Annexin V staining (PI/7-AAD negative) are in early stages of apoptosis. During late-stage apoptosis, loss of cell membrane integrity allows Annexin V binding to cytosolic PS, as well as cell uptake of PI and 7-AAD. Annexin V staining, paired with 7-AAD or PI is widely used to identify apoptotic stages by flow cytometry.

Host
E.coli

Conjugate
Biotin

Purity
> 98% pure

Molecular Mass
35.8 kDa

Reported Application
Flow Cytometric Analysis

Click-iT™ TUNEL Colorimetric IHC Detection Kit (Invitrogen™)

The Click-iT™ TUNEL Colorimetric IHC Detection Kit is used to identify apoptotic cells in tissue and cultured cell samples through the use of a small, highly specific labeling moiety and streptavidin-peroxidase conjugation. After incorporation of the labeling moiety into sites of DNA fragmentation, detection is achieved through a catalyzed "click" reaction that adds a biotin group at these sites. The subsequent addition of a streptavidin-peroxidase and peroxidase substrate results in a dark brown signal that can be detected with light microscopy and stored for future analysis.

Find more tools for image-based detection of apoptotic cells >

• Optimized for the detection of apoptotic cells in either tissue or cell samples
• Improved colorimetric TUNEL assay—better label incorporation due to small reactive moiety
• Increased sensitivity—specific label incorporation results in lower background and brighter signal
• Content-rich results—cell morphology, cellular environment, and apoptotic signal are clearly visible
• Flexibility—the assay can be configured for 50 independent TUNEL apoptosis tests

The later stages of apoptosis are characterized by changes in nuclear morphology, chromatin condensation, nuclear envelope degradation, and DNA fragmentation. Terminal deoxynucleotidyl transferase-dUTP nick end labeling (TUNEL) assays are based on the incorporation of modified dUTPs by terminal deoxynucleotidyl transferase (TdT) at the 3’-OH ends of fragmented DNA. Colorimetric TUNEL assays utilize dUTPs conjugated with a biotin moiety, followed by the addition of a streptavidin-peroxidase conjugate and peroxidase substrate, resulting in a dark brown apoptotic signal. However, colorimetric TUNEL assays are prone to high background, which reduces the sensitivity and specificity of the signal.

The Click-iT TUNEL Colorimetric IHC Detection Kit was developed to address these issues by utilizing a dUTP modified with an alkyne group (a small bio-orthogonal functional group) that enables the nucleotide to be more readily incorporated by TdT. After incorporation, a highly specific click reaction covalently links biotin azide and the alkyne group. Streptavidin-peroxidase (horseradish peroxidase) followed by peroxidase substrate (DAB) are added, allowing colorimetric detection of apoptotic cells. The high degree of labeling specificity inherent in the click technology results in low background and improved detection of apoptotic cells.

The Click-iT TUNEL Colorimetric IHC Detection Kit has been optimized and contains all of the reagents needed for detection of apoptotic cells from either tissue or cell samples. The reagents supplied in this kit can be used to test 50 samples and configured to test from one to 50 samples at a time.

eBioscience™ Annexin V Apoptosis Detection Set PE-Cyanine7 (Invitrogen™)

Annexins are a family of calcium-dependent phospholipid-binding proteins that preferentially bind phosphatidylserine (PS) in all mammalian species. Under normal physiologic conditions, PS is predominantly located in the inner leaflet of the plasma membrane. Upon initiation of apoptosis, PS loses its asymmetric distribution across the phospholipid bilayer and is translocated to the extracellular membrane leaflet marking cells as targets of phagocytosis. Once on the outer surface of the membrane, PS can be detected by fluorescently labeled Annexin V in a calcium-dependent manner.

In early-stage apoptosis, the plasma membrane excludes viability dyes such as propidium iodide (PI), 7-AAD, or Fixable Viability Dyes such as eFluor™ 660 or eFluor™ 780. These cells will stain with Annexin V but not a viability dye, thus distinguishing cells in early apoptosis. However, in late stage apoptosis, the cell membrane loses integrity thereby allowing Annexin V to also access PS in the interior of the cell. A viability dye can be used to resolve these late-stage apoptotic and necrotic cells (Annexin V, viability dye-positive) from the early-stage apoptotic cells (Annexin V positive, viability dye-negative).

Due to the emission spectrum of PE-Cyanine7, the Annexin V Apoptosis Detection Set PE-Cyanine7 is not compatible with propidium iodide and 7-AAD. It is recommended to substitute a Fixable Viability Dye such as eFluor™ 660 or eFluor™ 780 in their place.

Not included:
Fixable Viability Dye eFluor™ 660 (cat. 65-0864)
Fixable Viability Dye eFluor™ 780 (cat. 65-0865)

Note: Fixable Viability Dye eFluor™ 450 is not recommended for use with Annexin V Apoptosis Detection Kits.

Reactivity/Species
Human, Mouse, Rat

Reported Application
Flow Cytometric Analysis

Vybrant™ FAM Caspase-3 and -7 Assay Kit, for flow cytometry (Invitrogen™)

The Vybrant™ FAM Caspase-3 and -7 Assay Kit employs a novel approach to detect active caspases that is based on a fluorescent inhibitor of caspases (FLICA™) methodology, essentially an affinity label. The reagent associates a fluoromethyl ketone (FMK) moiety, which can react covalently with a cysteine, with a caspase-specific amine acid sequence. For caspase-3 and -7, this recognition sequence is aspartic acid-glutamic acid-valine-aspartic acid (DEVD). A fluorescein group is attached as a reporter. The FLICA reagent is thought to interact with the enzymatic reactive center of an activated caspase via the recognition sequence, and then to attach covalently through the FMK moiety. The FLICA inhibitor is cell permeant and noncytotoxic. Unbound FLICA molecules diffuse out of the cell and are washed away; the remaining green-fluorescent signal is a direct measure of the amount of active caspase that was present at the time the inhibitor was added. This kit includes the FLICA reagent specific for caspase-3 and -7, Hoechst 33342 stain, and propidium iodide stain, which allows the simultaneous evaluation of caspase activation, membrane permeability, and cell cycle by flow cytometry.

View a selection guide for all apoptosis assays for flow cytometry.

Click-iT™ TUNEL Alexa Fluor™ 594 Imaging Assay, for microscopy & HCS (Invitrogen™)

The Click-iT® TUNEL Alexa Fluor® 594 Imaging Assay utilizes a dUTP modified with an alkyne, a small, bio-orthogonal functional group that enables the nucleotide to be more readily incorporated by TdT than other modified nucleotides, including BrdUTP, biotin-dUTP or fluorescein-dUTP. Detection is based on a click reaction, a copper (I) catalyzed reaction between an azide and alkyne. Click chemistry fills the void when methods such as direct labeling or the use of antibodies are not efficient. The small size of the detection reagent, an Alexa Fluor® azide (MW <~1000) compared to that of an antibody (MW ~150,000) enables facile penetration of complex samples with only mild fixation and permeabilization required.

Compared to other assays using one of the other modified nucleotides, the Click-iT® TUNEL assay is able to detect a higher percentage of apoptotic cells under identical conditions. The assay is also fast and is complete within 2 hours. Furthermore, the Click-iT® TUNEL assay allows multiplexing with surface and intracellular biomarker detection.

More tools for apoptosis detection and measurement >

eBioscience™ Annexin V-FITC Apoptosis Detection Kit (Invitrogen™)

Annexins are a family of calcium-dependent phospholipid-binding proteins, which bind to phosphatidylserine (PS) to identify apoptotic cells. In healthy cells, PS is predominantly located along the cytosolic side of the plasma membrane. Upon initiation of apoptosis, PS loses its asymmetric distribution in the phospholipid bilayer and translocates to the extracellular membrane, which is detectable with fluorescently labeled Annexin V. In early stages of apoptosis, the plasma membrane excludes viability dyes such as propidium iodide (PI) and 7-AAD, therefore cells which display only Annexin V staining (PI/7-AAD negative) are in early stages of apoptosis. During late-stage apoptosis, loss of cell membrane integrity allows Annexin V binding to cytosolic PS, as well as cell uptake of PI and 7-AAD. Annexin V staining, paired with 7-AAD or PI is widely used to identify apoptotic stages by flow cytometry.

Host
E.coli

Conjugate
FITC

Laser
Blue Laser

Emit
520 nm

Excite
488 nm

Purity
> 98% pure

Molecular Mass
35.8 kDa

Reported Application
Flow Cytometric Analysis

Apoptotic DNA Ladder Kit (Invitrogen™)

The ApoTarget™ Quick Apoptotic DNA Ladder Detection Kit provides a simple and rapid procedure for extraction of chromosomal DNA. The procedure prepares DNA for use in the methods that detect DNA fragmentation in apoptotic cells. Unlike other kits requiring 1 to 2 days to finish, this detection method requires only less than 90 minutes to prepare DNA in a single tube without the need for extraction or column steps. DNA fragmentation can be easily visualized by agarose gel electrophoresis. This procedure increases recovery of small fragmented DNA, thereby improving the sensitivity of the assay.

Vybrant™ FAM Caspase-8 Assay Kit, for flow cytometry (Invitrogen™)

The Vybrant™ FAM Caspase-8 Assay Kit employs a novel approach to detect active caspases that is based on a fluorescent inhibitor of caspases (FLICA™) methodology, essentially an affinity label. The reagent associates a fluoromethyl ketone (FMK) moiety, which can react covalently with a cysteine, with a caspase-specific amine acid sequence. For caspase-8, this recognition sequence is leucine-glutamic acid-threonine-aspartic acid (LETD). A fluorescein group is attached as a reporter. The FLICA reagent is thought to interact with the enzymatic reactive center of an activated caspase via the recognition sequence, and then to attach covalently through the FMK moiety. The FLICA inhibitor is cell permeant and noncytotoxic. Unbound FLICA molecules diffuse out of the cell and are washed away; the remaining green-fluorescent signal is a direct measure of the amount of active caspase that was present at the time the inhibitor was added. This kit includes the FLICA reagent specific for caspase-8, Hoechst 33342 stain, and propidium iodide stain, which allows the simultaneous evaluation of caspase activation, membrane permeability, and cell cycle by flow cytometry.

View a selection guide for all apoptosis assays for flow cytometry.

Click-iT™ TUNEL Alexa Fluor™ 647 Imaging Assay, for microscopy & HCS (Invitrogen™)

The Click-iT® TUNEL Alexa Fluor® 647 Imaging Assay utilizes a dUTP modified with an alkyne, a small, bio-orthogonal functional group that enables the nucleotide to be more readily incorporated by TdT than other modified nucleotides, including BrdUTP, biotin-dUTP or fluorescein-dUTP. Detection is based on a click reaction, a copper (I) catalyzed reaction between an azide and alkyne. Click chemistry fills the void when methods such as direct labeling or the use of antibodies are not efficient. The small size of the detection reagent, an Alexa Fluor® azide (MW <~1000) compared to that of an antibody (MW ~150,000) enables facile penetration of complex samples with only mild fixation and permeabilization required.

Compared to other assays using one of the other modified nucleotides, the Click-iT® TUNEL assay is able to detect a higher percentage of apoptotic cells under identical conditions. The assay is also fast and is complete within 2 hours. Furthermore, the Click-iT® TUNEL assay allows multiplexing with surface and intracellular biomarker detection.

More tools for apoptosis detection and measurement >

Dead Cell Apoptosis Kit with Annexin V Alexa Fluor™ 488 & Propidium Iodide (PI) (Invitrogen™)

The Dead Cell Apoptosis Kit with Annexin V Alexa Fluor™ 488 & Propidium Iodide is a flow cytometry kit used to measure early apoptosis by detecting phosphatidyl serine expression and membrane permeability.

View a selection guide for all apoptosis assays for flow cytometry.

Superior brightness
Unlike other Annexin V kits that have lower protein concentrations or purification levels, the Annexin V Alexa Fluor™ 488 conjugate is optimized for flow cytometry to provide the largest separation between apoptotic and live cells. The Alexa Fluor™ 488 dye is a superior green-fluorescent dye with a spectrum similar to fluorescein (FITC).

High binding efficiency
Annexin V conjugates are made from a highly purified cys-annexin, which leads to higher binding efficiency, resulting in highly accurate characterization of the apoptotic process.

Multi-parametric
Many publications require a minimum of two different ways to identify that cells are apoptotic. This multi-parametric kit detects phosphatidyl serine (PS) on the cytoplasmic surface of the cell membrane and membrane integrity using propidium iodide.

How it works
When cells are stained with Annexin V and propidium iodide, apoptotic cells expressing PS show green fluorescence, which can be detected in the FITC channel, and low red fluorescence. Dead or necrotic cells show bright red fluorescence and no green fluorescence, while live cells show no green or red fluorescence.

eBioscience™ Annexin V Apoptosis Detection Kit PE (Invitrogen™)

Annexins are a family of calcium-dependent phospholipid-binding proteins that preferentially bind phosphatidylserine (PS). Under normal physiologic conditions, PS is predominantly located in the inner leaflet of the plasma membrane. Upon initiation of apoptosis, PS loses its asymmetric distribution across the phospholipid bilayer and is translocated to the extracellular membrane leaflet marking cells as targets of phagocytosis. Once on the outer surface of the membrane, PS can be detected by fluorescently labeled Annexin V in a calcium-dependent manner.

In early-stage apoptosis, the plasma membrane excludes viability dyes such as propidium iodide (PI), 7-AAD, or Fixable Viability Dyes such as eFluor™ 660 or eFluor™ 780. These cells will stain with Annexin V but not a viability dye, thus distinguishing cells in early apoptosis. However, in late stage apoptosis, the cell membrane loses integrity thereby allowing Annexin V to also access PS in the interior of the cell. A viability dye can be used to resolve these late-stage apoptotic and necrotic cells (Annexin V, viability dye-positive) from the early-stage apoptotic cells (Annexin V positive, viability dye-negative).

Note: Fixable Viability Dye eFluor™ 450 is not recommended for use with Annexin V Apoptosis Detection Kits.

Reported Application
Flow Cytometric Analysis

Mitochondrial Membrane Potential Apoptosis Kit, with Mitotracker™ Red & Annexin V Alexa Fluor™ 488, for flow cytometry (Invitrogen™)

This flow cytometry product provides a rapid and convenient assay for two hallmarks of apoptosis - phosphatidylserine externalization and changes in mitochondrial membrane potential. After staining a cell population with Alexa Fluor™ 488 annexin V and MitoTracker™ Red CMXRos dye in the provided binding buffer, live cells exhibit very little green fluorescence and bright red fluorescence, whereas apoptotic cells exhibit green fluorescence and decreased red fluorescence. These populations can easily be distinguished using a flow cytometer, and the 488 nm line of an argon-ion laser can be used to excite both dyes.

View a selection guide for all apoptosis assays for flow cytometry.

EnzChek™ Caspase-3 Assay Kit #2, Z-DEVD-R110 substrate (Invitrogen™)

The EnzChek® Caspase-3 Assay Kit #2 enables detection of apoptosis by providing a simple and reliable method for assaying caspase-3/7 activity. The kit can be used to continuously measure the activity of caspase-3/7 in cell extracts and purified enzyme preparations, using a fluorometer or fluorescence microplate reader.

See our complete line of Fluorescence Microplate assays.

• Fluorescent assay using standard fluorescein (FITC) excitation/emission settings
• Format allows for continuous measurement of caspase-3/7 activity in cell extracts
• Fluorescent and enzymatic controls included

The rhodamine 110-derived substrate (Z-DEVD-R110) used in this assay is a non-fluorescent bisamide compound that, upon enzymatic cleavage, is converted in a two-step process to the fluorescent monoamide and then to the even more fluorescent R110 product. Both of these hydrolysis products exhibit spectral properties similar to those of fluorescein, with peak excitation and emission wavelengths of 496 nm and 520 nm, respectively.

In addition to the Z-DEVD–R110 substrate, the EnzChek® Caspase Assay Kit #2 contains the reversible aldehyde inhibitor Ac-DEVD-CHO, as well as the reference standard R110. The Ac-DEVD-CHO inhibitor confirms that the fluorescence signals in both induced and control cell populations are due to the activity of caspase-3/7. The reference standard allows for quantification of the amount of R110 released in the reaction.

Hypoxia Green Reagent for Flow Cytometry

Hypoxia Green Reagent for Flow Cytometry is an antibody-independent reagent used to detect low levels of oxygen levels in live cells. The membrane-permeant probe releases rhodamine as oxygen levels decrease, resulting in a fluorogenic response. Hypoxia is a characteristic of many diseases, including cardiovascular disease and tumor-mediated immunosuppression and is critical to tumor survival and growth.

• Sensitive, fixed, end-point assay
• Detects decreases in oxygen in live cells
• Fluorogenic, non-antibody based probe