Methyl blue

Methyl blue
Identifiers
CAS number	28983-56-4
SMILES	[O-]S(=O)Oc1ccc(Nc2ccc(cc2)C (c3ccc(Nc4ccc(OS([O-])=O)cc4)cc3) =C5C=CC(C=C5)=[NH+]c6ccc(OS([O-])=O)cc6)cc1
Properties
Molecular formula	C37H27N3Na2O9S3
Molar mass	799.814 g/mol
Solubility in water	~ 300 g/l (20 °C)
Hazards
NFPA 704	1 1 0
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Methyl blue, also known as Cotton blue, Helvetia blue, Acid blue 93, or C.I. 42780, is a chemical compound with the molecular formula C₃₇H₂₇N₃Na₂O₉S₃. It is used as a stain in histology. Methyl blue stains collagen blue in tissue sections. It is soluble in water and slightly soluble in ethanol. It can be used in the Mallory's connective tissue stain and Gömöri trichrome stain. It is used in differential staining. It can also be used to mediate electron transfer in microbial fuel cells.

Methyl blue is also used to stain fungal cell walls. Methyl blue is also available in mixture with water blue, under name Aniline Blue WS, Aniline blue, China blue, or Soluble blue.

Methyl blue should not be confused with methyl violet or methylene blue, two other stains.

Methyl blue is also used to treat thallium poisoning. It binds to the thallium.

See also

• Potassium ferrocyanide
• Potassium ferricyanide
• Methylene blue
• Egyptian Blue
• Han Purple
• Gentian violet
• Fluorescein

References

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