CellBrite™ Fix dyes are fluorogenic membrane dyes that covalently stain the plasma membrane in live cells. They are unique among membrane stains in which they can withstand both fixation and detergent permeabilisation.

• Withstands fixation and permeabilisation
• Bright, uniform cell surface staining in 15 minutes
• Available with green, red and far-red fluorescence
• Stain provided in lyophilised format
• Each vial makes 20 μl of 1000X dye

These dyes are a series of proprietary fluorophores to rapidly stain the outer plasma membranes of live cells. Stains are unique in that their surface staining can withstand permeabilisation and methanol fixation, allowing plasma membrane staining to be combined with intracellular staining with antibodies. Unlike lectins such as WGA, which bind specific targets that may vary between cell types, this CellBrite™ dyes are general membrane stains.

They are amine-reactive and are designed to accumulate at the cell membrane, and they become covalently attached to membrane proteins. As a result, surface staining is well-retained after permeabilisation or methanol fixation, with only a slight increase in intracellular fluorescence compared to formaldehyde fixation alone. They are weakly fluorescent in aqueous media but become intensely fluorescent upon membrane staining. This fluorogenic property of the dyes makes the staining very specific with low background. Due to their better water solubility, CellBrite™ Fix dyes yield much more uniform staining compared to lipophilic carbocyanine dyes, like DiO and DiI. The dyes are non-cytotoxic and do not readily transfer between cells. They also can be used to stain yeast and bacteria (gram-positive or gram-negative).