The cell stain kit can be used to determine cell viability prior to intracellular antibody staining, or for the elimination of hazardous substances using formaldehyde fixation. This kit has been optimized and validated for use with a violet laser flow cytometer. Dyes are freeze dried in separate vials to maintain stability.
Staining pattern is the same before and after fixation. Minimal spectral overlap between other fluorophores. The cell staining equipment is packaged in convenient 40-test vials, which are not available in solution. This helps to ensure the dye's stability and performance over time. The effectiveness of amine reactive dyes in solutions will decrease over time.
It is best to use the vial immediately after rehydrating. If it is impossible to do so, you can aliquot vials and keep them at -80C. Fixable cell stain binds covalently with intracellular and extracellular aminos. The staining pattern can be preserved after formaldehyde fixation.
The excitation limit for the aqua-fluorescent reactive dye is 375 nm. However, it can be excited well by the 405 nm violet light laser. In cells with compromised membranes the dye reacts with both the cell interior and the cell surface to produce intense fluorescent staining. The dye's reactivity in viable cells is limited to cell-surface amines.
This results in less intense fluorescence. It is possible to distinguish between dead and live cells by the difference in intensity, which is usually greater than 50-fold.