Product Description
Cell Counting Kit-8 (CCK-8) allows sensitive colorimetric assays for the determination of cell viability in cell proliferation and cytotoxicity assays.
The CCK-8 solution contains WST-8 [2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-
(2,4-disulfophenyl)-2H-tetrazolium, monosodium salt], a compound similar to MTT. Under the presence of the electron coupling reagent 1-Methoxy PMS, WST-8 is reduced by mitochondrial dehydrogenases to form a highly water-soluble orange-yellow formazan product (see Figure 1). The amount of formazan generated is directly proportional to the number of living cells. Thus, this characteristic allows for direct analysis of cell proliferation and toxicity; more rapid cell proliferation results in a darker color, while greater cell toxicity yields a lighter color.
Compared to previous proliferation/toxicity assays, CCK-8 offers distinct advantages (see Table 1). CCK-8 features high sensitivity, short reaction time, wide linear range, reliable data, and good reproducibility, making it widely applicable for drug screening, cell proliferation assays, cytotoxicity assays, and tumor drug sensitivity tests.
Table 1. Comparison of Proliferation/Toxicity Assay Reagents
Assay Method | MTT | XTT | WST-1 | CCK-8 |
Solubility of Formazan | Poor (requires organic solvents) | Good | Good | Good |
Sensitivity | High | Very High | Very High | Highest |
Assay Time | Longer | Shorter | Shorter | Shortest |
Detection Wavelength | 560-600nm | 420-480nm | 420-480nm | 430-490nm |
Cytotoxicity | High, complete loss of cell morphology | Very Low, no change in cell morphology | Very Low, no change in cell morphology | Very Low, no change in cell morphology |
Reagent Stability | Average | Poor | Average | Very Good |
Suitability for Batch Sample Testing | Yes | Very Suitable | Very Suitable | Very Suitable |
Convenience | Average | Convenient | Convenient | Very Convenient |
Shipping and Storage
- Storage:Store at 2-8℃ in dark until the expiry date stated on the label. (Store it at -20°C for longer storage. Repeated thawing and freezing causes an increase in the background, which interferes with the assay. Please store the kit at 0-5oC for frequent use.)
- Shipping:
Usage Statement
Research Use Only (RUO)
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