Shop All Cytotoxicity Assay Kits

LIVE/DEAD™ Cell-Mediated Cytotoxicity Kit, for animal cells (Invitrogen™)

The LIVE/DEAD® Cell-Mediated Cytotoxicity Kit measures natural killer (NK) cell-mediated, lymphokine-activated killer (LAK) cell-mediated and T cell mediated cytotoxicity. Target cells are preincubated with the green-fluorescent membrane stain DiOC18 and then mixed with effector cells in the presence of the red-fluorescent, membrane-impermeant dye, propidium iodide. Live and dead target cells retain the green-fluorescent membrane stain; target and effector cells with compromised membranes exhibit red-fluorescent nucleic acid staining; live effector cells are nonfluorescent.

CyQUANT™ LDH Cytotoxicity Assay (Invitrogen™)

The CyQUANT LDH Cytotoxicity Assay is a colorimetric assay that provides a simple and reliable method for determining cellular cytotoxicity. Lactate dehydrogenase (LDH) is a cytosolic enzyme present in many different cell types that is released into the cell culture medium upon damage to the plasma membrane. The CyQUANT LDH Cytotoxicity Assay provides the reagents to accurately and quantitatively measure this extracellular LDH.

Note: The CyQUANT LDH Cytotoxicity Assay (Cat. Nos. C20300 and C20301) are direct replacements for the Pierce LDH Cytotoxicity Assay Kit (Cat. Nos. 88953 and 88954).

CyQUANT LDH Cytotoxicity Assay features include:
Convenient—add-mix-read assay format for adherent and suspension cells, including 3D cell models
Accurate—provides a quantitative measurement of LDH release
Flexible—ideal for high-throughput screening, monitor cytotoxicity from the same sample over time
Robust—uses stable LDH enzyme activity as a cytotoxic marker

LDH is a cytosolic enzyme present in many different cell types and is a well-established and reliable indicator of cellular toxicity. Damage of the plasma membrane results in a release of LDH into the surrounding cell culture medium. This extracellular LDH can be quantified by a coupled enzymatic reaction in which LDH catalyzes the conversion of lactate to pyruvate via NAD+ reduction to NADH. Diaphorase then uses NADH to reduce a tetrazolium salt (INT) to a red formazan product that can be measured at 490 nm. The level of formazan formation is directly proportional to the amount of LDH released into the medium.

The CyQUANT LDH Cytotoxicity Assay provides the reagents needed for the simple, reliable colorimetric quantification of cellular cytotoxicity. The kit can be used with different cell types, including 3D cell models, to measure cytotoxicity mediated by chemical compounds as well as cell-mediated cytotoxicity. Since LDH in the medium is the indicator of cellular cytotoxicity, the assay can be used to monitor cytotoxicity from the same sample over time. To perform the assay, an aliquot of the cell culture medium is transferred to a new plate and the reaction mixture is added. After a 30-minute incubation, the reaction is stopped by adding Stop Solution and absorbance is measured using a microplate reader.

CyQUANT™ LDH Cytotoxicity Assay, fluorescence (Invitrogen™)

The CyQUANT LDH Cytotoxicity Assay, fluorescence, is a fluorescent assay that provides a simple and reliable method for determining cellular cytotoxicity. Lactate dehydrogenase (LDH) is a cytosolic enzyme present in many different cell types that is released into the cell culture medium upon damage to the plasma membrane. The CyQUANT LDH Cytotoxicity Assay, fluorescence, provides the reagents to accurately and quantitatively measure this extracellular LDH.

The CyQUANT LDH Cytotoxicity Assay, fluorescence, features include:
Convenient—add-mix-read assay protocol for adherent and suspension cells, including 3D cell models
Accurate—provides a quantitative measurement of LDH release
Flexible—ideal for high-throughput screening, monitor cytotoxicity from the same sample over time
Robust—formulation with highly purified resazurin results in a large assay dynamic range

LDH is a cytosolic enzyme present in many different cell types and is a well-established and reliable indicator of cellular toxicity. Damage of the plasma membrane results in a release of LDH into the surrounding cell culture medium. This extracellular LDH can be quantified by a coupled enzymatic reaction in which LDH catalyzes the conversion of lactate to pyruvate via NAD+ reduction to NADH. Diaphorase then uses NADH to reduce resazurin to resorufin that can be detected using an excitation of 560 nm and emission of 590 nm. The level of resorufin formation is directly proportional to the amount of LDH released into the medium.

As a consequence of the synthesis and manufacturing processes, all resazurin-based reagents contain a detectable amount of resorufin contamination. The amount of contamination can vary greatly between sources of the material and manufacturing conditions, contributing to differences in detectable background fluorescence. More importantly, the contaminating resorufin reduces the signal to background ratio and dynamic range of the assay. An innovative process was developed that removes the contaminating resorufin, resulting in the highly pure resazurin used in the CyQUANT™ LDH Cytotoxicity Assay, fluorescence.

The CyQUANT LDH Cytotoxicity Assay, fluorescence, provides the reagents needed for the simple, reliable fluorescence-based quantification of cellular cytotoxicity. The kit can be used with different cell types, including 3D cell models, to measure cytotoxicity mediated by chemical compounds as well as cell-mediated cytotoxicity. Since LDH in the medium is the indicator of cellular cytotoxicity, the assay can be used to monitor cytotoxicity from the same sample over time. To perform the assay, an aliquot of the cell culture medium is transferred to a new plate and the reaction mixture is added. After a 10-minute incubation, the reaction is stopped by adding Stop Solution and fluorescence is measured using a microplate reader.

CyQUANT™ Cytotoxicity Assay Kit (G6PD Release Assay) (Invitrogen™)

In the CyQUANT Cytotoxicity Assay Kit, damaged and dying cells release glucose 6-phosphate into surrounding medium. The glucose 6-phosphate is detected by an enzymatic process that leads to the reduction of resazurin into red-fluorescent resorufin. This assay can detect as few as 500 cells and is more sensitive than LDH release assays.

6-NBDG (6-(N-(7-Nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-6-Deoxyglucose) (Invitrogen™)

6-NBDG is a fluorescent nonhydrolyzable glucose analog that has been used to monitor glucose uptake and transport in live cells. Although sensitive to its environment NBD fluorescence typically displays excitation/emission maxima of ~465/540 nm and can be visualized using optical filters designed for fluorescein.