L'excellence biotechnologique

MTS Cell Proliferation Colorimetric Assay Kit

The MTS Cell Proliferation Colorimetric Assay Kit (by AffiGEN) is a reliable, non-radioactive method designed for quantifying viable cells in proliferation or cytotoxicity assays. This kit leverages the bioreduction of MTS tetrazolium compound into a formazan product that is soluble in culture media. The production of formazan is proportional to the number of metabolically active cells, allowing for sensitive detection of viable cell populations.

Principle of the Assay

The MTS assay is based on the reduction of the MTS tetrazolium compound (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) by mitochondrial dehydrogenases in viable cells into a colored formazan product. This process occurs only in metabolically active cells, making it a strong indicator of cell viability. The absorbance of the formazan dye is measured at 490 nm, which correlates directly with cell number.

📚 Reference: Buttke & Sandstrom, 1994 — MTS assays are discussed as sensitive indicators of cell metabolic activity.

Advantages

• Non-radioactive, safe for routine lab use.
• One-step procedure, no solubilization required.
• High-throughput compatible, suitable for 96-well and 384-well formats.
• Compatible with a wide variety of cell types, including cancer, stem, and primary cells.
• Allows continuous monitoring of cell proliferation without disrupting culture.

🔗 See a comparative study on tetrazolium-based viability assays: Berridge et al., 2005

Applications

• Cell proliferation studies
• Drug cytotoxicity testing
• Chemotherapeutic screening
• Growth factor stimulation assays

Scientific Validation

The MTS assay has been extensively validated across biomedical research and is cited in numerous scientific publications. Its high correlation with other cell viability assays, such as MTT and XTT, ensures data consistency and reliability.

🔍 For an in-depth review on cytotoxicity assays, see:

• Riss et al., 2016, Assay Guidance Manual by NIH.
• Stockert et al., 2018, discussing limitations and comparisons with other colorimetric assays.

Protocol Summary

1. Seed cells into the desired well format.
2. Incubate for 24 hours (or until cells reach desired confluency).
3. Add MTS reagent (20 μL per 100 μL of medium).
4. Incubate for 1–4 hours at 37°C.
5. Measure absorbance at 490 nm using a plate reader.

For complete details, consult peer-reviewed examples using MTS:

• Zhao et al., 2014: MTS in apoptosis and viability studies.
• Yang et al., 2019: Drug screening using MTS-based readouts.

Safety and Compatibility

The assay is compatible with phenol red-containing media, although blank correction is recommended. It does not require organic solvents, making it safer than traditional MTT assays.

🔗 NIH Chemical Safety Sheet on MTS Reagent

.