MTT Reagent: Assessing Cell Metabolic Activity

Cellular metabolic activity is a crucial parameter in various fields of research, including pharmacology, toxicology, and cell biology. The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay is a widely used method for assessing cell metabolic activity. This article provides an overview of the MTT assay, its principle, and its applications.

Principle of the MTT Assay

The MTT assay is based on the ability of cellular oxidoreductase enzymes to reduce MTT to its insoluble formazan product, which exhibits a purple color. This reduction occurs in metabolically active cells and is proportional to the number of viable cells present in the culture.

The MTT assay is a colorimetric analysis that relies on the reduction of MTT by NADPH-dependent cellular oxidoreductase enzymes. The reduction of MTT to formazan can be measured spectrophotometrically and provides a quantitative assessment of cell metabolic activity.

Application and Advantages

The MTT assay is widely used in cell viability studies and drug discovery research. It allows researchers to assess the cytotoxicity or cytostatic activity of potential medicinal agents and toxic materials.

The MTT assay offers several advantages over other cell viability assays. It is relatively simple to perform, cost-effective, and provides reliable results. Additionally, the assay can be adapted to measure cell metabolic activity in various cell types and experimental conditions.

Tetrazolium Dyes and Alternative Assays

MTT is a yellow tetrazole that is reduced to a purple formazan product in living cells. Besides MTT, other tetrazolium dyes such as XTT, MTS, and WSTs are also commonly used in conjunction with intermediate electron acceptors to assess cell metabolic activity.

Alternative assays, such as the ATP-based CellTiter-Glo® Luminescent Cell Viability Assay, have been developed to overcome certain limitations of the MTT assay. These alternative assays provide additional information on cell viability and metabolic activity by directly measuring ATP levels, which is a more direct indicator of cell health.

Conclusion

The MTT assay is a valuable tool for assessing cell metabolic activity and cell viability in various research fields. Its simplicity, cost-effectiveness, and reliable results make it a popular choice for many researchers. However, it is important to consider the specific requirements of the experiment and explore alternative assays when necessary.

Sources

1. MTT Assay – an overview. Retrieved from https://www.sciencedirect.com/topics/neuroscience/mtt-assay
2. MTT assay – Wikipedia. Retrieved from https://en.wikipedia.org/wiki/MTT_assay
3. Is Your MTT Assay the Right Choice? Retrieved from https://www.promega.com/resources/pubhub/is-your-mtt-assay-really-the-best-choice/

FAQs

What is the MTT assay and what does it measure?

The MTT assay is a tetrazolium dye assay used to assess cell metabolic activity. It measures the ability of cellular oxidoreductase enzymes to reduce MTT to its insoluble formazan, which has a purple color.

How does the MTT assay work?

The MTT assay is a colorimetric analysis that relies on the reduction of MTT by NADPH-dependent cellular oxidoreductase enzymes. The reduction of MTT to formazan is proportional to the number of viable cells present.

What are tetrazolium dyes and how are they used in the MTT assay?

Tetrazolium dyes, such as MTT, are yellow compounds that are reduced to colored formazan products in living cells. In the MTT assay, MTT is added to the cells, and its reduction to formazan is measured to assess cell metabolic activity.

How is the MTT assay performed and how is the result measured?

In the MTT assay, after MTT reduction, the insoluble formazan product is dissolved using a solubilization solution. The absorbance of the colored solution can be quantified by measuring at a specific wavelength using a spectrophotometer.

What does the MTT assay tell us about cell viability?

The amount of formazan produced in the MTT assay is directly proportional to the number of living cells present in the culture. Therefore, the MTT assay allows for the calculation of cell viability based on the metabolic activity of the cells.

What are the applications of the MTT assay?

The MTT assay is commonly used to assess cytotoxicity or cytostatic activity of potential medicinal agents and toxic materials. It is widely employed in drug discovery research and various fields of cell biology.

Are there alternative assays to the MTT assay?

Yes, there are alternative assays available to assess cell viability and metabolic activity. One example is the ATP-based CellTiter-Glo® Luminescent Cell Viability Assay, which directly measures ATP levels as an indicator of cell health.

What are the advantages of using the MTT assay?

The MTT assay offers several advantages, including its simplicity, cost-effectiveness, and reliable results. It can be adapted to measure cell metabolic activity in different cell types and experimental conditions, making it a popular choice for many researchers.