XTT Cell Viability Assay Protocol

Metabolic activity—based cell viability assay
XTT is a colorimetric assay used to assess cell viability as a function of cell number based on metabolic activity. This rapid, sensitive, non-radioactive assay is detected using standard microplate absorbance readers.
This protocol can be used for:
- Quantification of cell number based on metabolic activity in microplates
This protocol should not be used for:
- Fluorescence microscopy
You will need the following for this protocol:
- Cells growing in culture
- XTT (Cat. No. X-6493)
- Cell culture medium
- Phosphate-buffered saline (Cat. No. 10010-023)
- Phenazine methosulfate (PMS) (Fisher Cat. No. AC130160010)
- 96-well plates
- Microplate reader
- CO2 incubator
Protocol
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Protocol tips
- XTT dissolves more quickly if the culture medium is warmed to 37°C
- Washing is not required after staining
- Store remaining PMS solution at –20°C
- A cell titration experiment using a range of cells from 103–105 cells/well can be used to generate a standard curve
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For Research Use Only. Not for use in diagnostic procedures.