ViaKrome Fixable Viability Dye Assay Principle

ViaKrome fixable viability dyes bind to reactive thiols.  These dyes are cell membrane impermeant.  Therefore in living cells the proteins on the cell surface are accessible to take part in the reaction.  Cells with compromised membranes will allow the dye to diffuse inside the cell where it can interact with a larger concentration of reactive proteins.  This results in dead cells staining brighter than live cells.  Furthermore, this staining pattern can be preserved by fixation, a process required for intracellular marker staining.

Fixable Viability Dye Assay Principle