Cell Counting Kit-8 (CCK-8) allows sensitive colorimetric assays for the determination of cell viability in cell proliferation and cytotoxicity assays. Dojindo’s highly water-soluble tetrazolium salt, WST-8, is reduced by dehydrogenase activities in cells to give a yellow-color formazan dye, which is soluble in the tissue culture media. The amount of the formazan dye, generated by the activities of dehydrogenases in cells, is directly proportional to the number of living cells. The detection sensitivity of CCK-8 is higher than the other tetrazolium salts such as MTT, XTT, MTS or WST-1.
Cell viability detection mechanism with CCK-8
Cell Counting Kit-8 requires 3 simple steps.
The handling time of Cell Counting Kit-8 is the shortest among it’s competitors. Only 15 minutes of handling time for Cell Counting Kit-8 where as longer handling time is required for both MTS and MTT assay.
Cell Counting Kit-8 is a ready-to-use solution. It is also stabe at 4ºC for 1 year. Your assay can be done anytime without thaw and freeze.
CCK-8 (WST-8) is the highest sensitive dye for the cell based assay.
Comparison of the sensitivity using tetrazolium dye
Cytotoxicity of Reagents
Only in CCK-8, continious culture is possible without killing cells.
Observation of Cytotoxicity after incubation with each reagent.
HeLa cells were incubated with WST-8 (CCK-8), WST-1, or MTS at 24 hours from addition of those reagents.
Example Data using Cell Counting Kit-8
Data for Cell Proliferation and Cytotoxicity Assay
Absorption property of WST-8
The microplate reader with a 450-490 nm filter is applicable for the measurement.
Absorption spectrum of WST-8 formazan dye