Safranin

Safranin is a biological stain used in histology and cytology. Safranin is used as a counterstain in some staining protocols, colouring all cell nuclei red. This stain is also often used in the Gram stain protocol, staining Gram-negative bacteria red or pink. It is a red, azo dye that is used for staining the nuclei of cells, making it easier to identify and study them.

History

Safranin was first synthesized by the German chemist Carl Graebe in 1876. It was originally used as a dye for textiles, but was later adopted for use in biological staining due to its ability to bind to and highlight certain structures in cells and tissues.

Uses

Safranin is primarily used in the field of microbiology as a counterstain in the Gram stain procedure. After the application of the primary stain (crystal violet), the safranin is applied. The safranin stains the Gram-negative bacteria, which have thinner cell walls that do not retain the crystal violet stain.

In addition to its use in the Gram stain, safranin is also used in the endospore stain procedure. In this procedure, it is used to stain vegetative cells, while a different stain (malachite green) is used to stain the endospores.

Safranin is also used in the field of botany for the staining of lignin in sections of plant tissues. It is used in combination with other stains to provide contrast and allow for the differentiation of different structures within the plant tissues.

Safety

As with all chemical substances, care should be taken when handling safranin. It is a potential skin and eye irritant, and should be handled with gloves and eye protection. In case of contact with the skin or eyes, rinse immediately with plenty of water.

See also

• Gram stain
• Endospore stain
• Histology
• Cytology

Safranin Resources
Latest articles Most recent articles Ongoing trials	Wikipedia