Our product Cell Counting Kit-8 (CCK-8) provide a more convenient and sensitive method for the research of cell number determination and cell proliferationtotoxicity assay than previous ways. The kit utilizes a highly water-soluble tetrazolium salt, WST-8, which produces a water-soluble formazan dye upon reduction in the presence of an electron mediator. The amount of the formazan generated by dehydrogenases is directly in proportion to the numbers of living cells. The detection sensitivity by CCK-8 is higher than other tetrazolium salts such as MTT, XTT, MTS or WST-1. Other sizes are available. Please inqury us for quote.