WST-8

WST-8 (2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H tetrazolium, monosodium salt), a highly stable and water-soluble WST, is utilized incell Counting Kit-8 (CCK-8).It is more sensitive than WST-1 particularly at neutralpH. Because of the electron mediator, 1-methoxy PMSin this kit is highly stable, and CCK-8 is stable for at least six months at the room temperature and for one year at 0-5°C (asshown in Figure 1).Advantages: WST-8 is not cell permeable, which results in low cytotoxicity. Therefore,after the assay, it is possible to continue further experiments using the same cells.Furthermore, it produces the water-soluble formazan upon cellular reduction，which would provide an additional advantage to the method by allowing a simpler assay procedure and not required an extra step to dissolve the formazan.Disadvantages: An important consideration is that reduction of assay substrates isimpacted by changes in intracellular metabolic activity that has no direct effect on over-all cell viability.
WST-8 (Water-Soluble Tetrazolium 8) is a water-soluble tetrazolium salt widely used to assess the metabolic activity of cells. The dye does not penetrate living cells but can be reduced outside the cells by NADPH-dependent cellular oxidoreductases to water-soluble formazan. The reaction occurs by electron transfer across the plasma membrane in a neutral pH and the presence of an intermediate electron acceptor,1-methoxyphenazine methosulfate. The staining intensity is proportional to the number of viable cells. The maximum absorption of the reaction product is 450–500 nm.The use of WST-8 hasseveral advantages:We also supply WST-8 as a ready-to-use kit for cell proliferation assay.