"CCK-8" stands for "Cell Counting Kit-8". The mechanism is similar to MTT test, but here the dye used is water soluble and is called: WST-8 (2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium, monosodium salt). WST-8 is bioreduced by cellular dehydrogenases to an orange formazan product that is soluble in tissue culture medium. The amount of formazan produced is directly proportional to the number of living cells.
Procedure:
Manual
Assay Sensitivity
Source: https://www.dojindo.eu.com/store/p/456-Cell-Counting-Kit-8.aspx
