For fluorometric determination of the number of living cells present in the given samples, the Cell counting Kit or CCK is used. The number of viable cells in a culture medium directly correlates to how much calcein is produced from calcein by esterases. Calcein-AM is highly lypohilic due to the acetoxymethy group in the molecule.
It can quickly permeate into cells through the cell membrane. CCK does not require radioisotopes, such as the thymidine incorporated test or a solubilization process. It allows users to get highly reproducible and precise results in cell proliferation assays. Cell counting equipment allows for sensitive colorimetric assays to determine cell viability in cell proliferation as well as cytotoxicity.
WST-8 is a water-soluble tetrazolium sodium salt. It is reduced in cells by dehydrogenase activity to produce a yellow-colored formazan dye. This dye is soluble in tissue culture media. The number of cells that have formed formazan dye is directly proportional with the amount of active dehydrogenases.
CCK-8 has a higher detection sensitivity than other tetrazolium sodium salts, such as MTT and XTT or MTS, but it is still sensitive to WST-1. The Cell Counting Kit-8 is a single-bottle kit and does not require any premixing. This sensitive, non-radioactive colorimetric assay can accurately count live cells in cell proliferation and cytotoxicity assays.
Cell Counting Kit-8 provides sensitive colorimetric assays to determine the number of viable cells for both proliferation and cytotoxicity tests. The detection sensitivity of Cell Counting Kit-8 is greater than that of other tetrazolium sodium salts like MTT, MTS, XTT and MTS. This kit is very easy to use for assays water-soluble Tetrazolium salt is recommended.