Trypan blue is an azo dye, derived from toluidine. It is also known as diamine blue and Niagara blue. It is widely used as a vital stain to distinguish the viable cells from
the non-viable cells. It selectively stains the dead tissues or cells blue in colour. Live cells or tissues, with intact cell membrane, are not coloured and are very selective in the compounds that pass through the membrane as a result of which trypan blue is not absorbed by viable cells. However, it can pass through the cell membrane in a dead cell and so dead cells appear blue in colour under a microscope. Live cells are excluded from staining so this staining method is also described as a dye exclusion method.

Trypan blue is most commonly used in microscopy for cell counting. TCL005 is 0.5% solution of Trypan blue in Dulbecco’s Phosphate Buffered Saline.

Storage and Shelf Life

• Store at 15-30ºC.
• Shelf life of the product is 24 months.
• Use before expiry date given on the product label.

Sterility

No bacterial or fungal growth is observed after 14 days of incubation, as per USP specification.