Nile red

• 7 -diethylamino- 3,4- benzophenoxazine -2-one
• Nile blue Oxazon
• Phenoxazone 660
• Phenoxazone 9

Dark green solid

Fixed

203-205 ° C

Template: Infobox chemical / molecular formula search available

Nile Red, Nile Blue Oxazon also called, is a lipophilic fluorescent dye, phenoxazine.

Production

Nile red is produced by boiling a solution of Nile blue with sulfuric acid. The amino group is replaced by a carbonyl group.

Properties and Uses

Nile red is a highly fluorescent laser dye. It fluoresces in the red region well into the near-infrared ( NIR) and has an emission maximum at about 650 nm, both the emission maximum and the quantum yield are strongly dependent on the solvent used. In n-heptane, the emission maximum is at about 520 nm, on the other hand in acetone at 600 nm The fluorescence is about 80 times weaker in acetone. A higher polarity of the solvent generally leads to a red shift of the fluorescence maximum and a decrease in the quantum yield and the fluorescence lifetime of Nile red.

In microbiology, Nile Red is for marking and staining (English staining ) of cells or cell components used. The fluorescence is dependent on the hydrophobicity of the lipids. Polar, ie more hydrophilic lipids, such as phospholipids, which are located in the cell membrane, in essence, fluoresce red. Neutral lipids, such as triglycerides or cholesterol esters in intracellular lipid droplets, whereas fluoresce at shorter wavelengths ( towards yellow ). The fluorescence can be measured microscopically, as well as by flow cytometry.

Nile red is used in biochemistry for staining proteins in the course of a protein characterization, for example, in SDS -PAGE and isoelectric focusing.