Merck, T6146-25G, Trypan Blue

General description
The trypan blue dye is an azo dye, derived from toluidine. It is soluble in water and has a molecular weight of 961 g/mol.
Application
Trypan blue has been used:

in cell viability assay
to stain plant tissue in order to to visualize cell death

Biochem/physiol Actions
The trypan blue dye is useful to differentiate the dead and live cells based on the cell′s ability to take up or exclude the dye. A viable cell is assumed to possess an intact cell membrane and hence excludes this dye and the cytoplasm appears clear. While on the other hand non-viable cells shows a blue cytoplasm.
Preparation Note
To make a cell viability solution, add the T6146 Trypan Blue powder to a clean and dry glass or plastic container of appropriate capacity. Add a suitable solvent, such as sterile distilled water, to the container with the Trypan Blue powder. Stir the solution vigorously using a stir bar or a glass rod until the powder has completely dissolved. A 0.4% solution is a common concentration for typical cell viability assessment. For example, to make 100 mL of a 0.4% solution, add 400 milligrams (0.4 g) to 99.6 mL solvent.