XTT Cell Viability Assay Protocol

Specific for: XTT Cell Viability Kit #9095.

A. Reagent Preparation

1. Thaw reagents just before experiment.

NOTE: Precipitation may occur when reagents are stored at −20°C. Make sure reagents are clear prior to use. If necessary, warm reagents to 37°C to reconstitute.

2. Add electron coupling solution to XTT Reagent (1:50 volume ratio) to make XTT detection solution. For example, each 96-well plate needs 5 ml XTT solution and 0.1 ml electron coupling solution.

B. XTT Assay

1. Add 50 µl XTT detection solution to each well of 96-well plate (which contains 100–200 µl/well culture medium) and return plate to incubator.
2. Read absorbance at 450 nm.

NOTE: The optimal incubation time for this assay depends on experimental setup, such as: cell type, cell number, and treatment. Optimization of incubation time can be determined by reading one plate at various time points after addition of XTT detection solution (featured below).