CCK8are

CCK8are is a term occasionally used to refer to the CCK-8 assay, a colorimetric method for assessing cell viability and proliferation in vitro. It uses the water-soluble tetrazolium salt WST-8, which is reduced by cellular dehydrogenases in viable cells in the presence of an electron mediator to form a yellow-orange formazan dye. The amount of formazan dye generated is proportional to the number of living cells, allowing quantification by measuring absorbance at 450 nm (with a reference at 630 nm).

Protocol typically involves seeding cells in a microplate, adding the CCK-8 reagent, incubating for 1–4 hours, and reading absorbance with a microplate reader. The assay is generally more convenient than the MTT or XTT assays because the formazan product is water-soluble and does not require a solubilization step, enabling easier throughput and faster results.

Advantages of the CCK-8 assay include high sensitivity, low toxicity to cells, simplicity, and suitability for high-throughput screening. Limitations include a nonlinear response at high cell densities, potential interference from certain media components or phenol red, and variability among cell types due to metabolic rate. Proper controls and calibration are advised to ensure accurate interpretation of results.

Common applications cover cell viability and cytotoxicity testing, proliferation assays, and drug screening across diverse cell lines and experimental conditions. The method was developed and popularized as part of the Dojindo Cell Counting Kit series and remains widely used in biomedical research.