Methyl Blue (Cotton Blue) C.I. 42780



Methyl Blue, also known as Cotton blue, acid blue 93 and china blue and is commonly used as a counterstain in the martius scarlet blue and masson trichrome staining methods.


Minimum Assay: 96%
Molecular Formula: C32H25N3O9S3Na2
Molecular Weight: 737.74 g/mol
Melting Point: 137 °C
Absorption max: 600 nm
Visual transition: pH 10.0 (blue) to pH 13.0 (orange)

Hazard Phrases: Harmful if swallowed.

Prec Phrases: Avoid breathing dust/fume/gas/mist/vapours/spray. IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.

Cas No: 28983-56-4
Einecs No: 249-352-9

HS CODE: 3822000000


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