METANIL YELLOW

Description

Metanil yellow is a yellow monoazo dye. This coloring agent is used in leather and wood stains, and was also employed as a food dye in India.

Chemical properties

orange powder

The Uses of METANIL YELLOW

Metanil Yellow is used as indicator. Metanil yellow is useful in spectrophotometric methods to determine the presence of trace amounts of nitrates and nitrites in solution. The method utilizes the fact that potassium bromate can catalyze the discoloring of Metanil yellow which can then be analyzed by spectrophotometry.

The Uses of METANIL YELLOW

As indicator in 0.1% solution, of which 2 drops are required for 10 ml liquid. pH: 1.2 red to 2.3 yellow.

The Uses of METANIL YELLOW

dye used in leather; as indicator (pH) in laboratories

What are the applications of Application

Metanil yellow is a microscopy stain and pH indicator

Definition

ChEBI: An organic sodium salt having 3-[(4-anilinophenyl)diazenyl]benzene-1-sulfonate as the counterion. Used in one variant of Masson's trichrome to stain collagen yellow in contrast to the red muscle, but is not in common used.

General Description

Metanil yellow is an azo dye, which is used as a counterstain in PAS (periodic acid-Schiff) or iron-hematoxylin stained sections to increase contrast. At pH 1.2, metanil yellow is red in color, whereas in pH 2.3, it is yellow in color.

Flammability and Explosibility

Not classified

Contact allergens

Metanil yellow is a yellow monoazoic dye. This color ing agent is used in leather and wood stains, and is also employed as a food dye in India.

Biochem/physiol Actions

Metanil yellow is an azo dye. It is used as a counterstain in PAS (periodic acid-Schiff)/iron-hematoxylin stained sections to increase contrast. Metanil yellow changes its color from red at pH 1.2 to yellow at pH 2.3.

Safety Profile

Moderately toxic by intraperitoneal route. Experimental reproductive effects. Human mutation data reported. When heated to decomposition it emits toxic fumes of SOx, NOx, and NazO. See also AROMATIC AMINES and SULFONATES.

Purification Methods

It can be salted out from water three times with sodium acetate, then repeatedly extracted with EtOH [McGrew & Schneider J Am Chem Soc 72 2547 1950]. [Beilstein 16 II 168.]

Properties and Applications

Standard	Light Fastness	Soaping		Persperation Fastness	Oxygen bleaching		Fastness to seawater
		Fading	Stain		Fading	Stain	Fading	Stain
ISO	3	2		2-3
AATCC	3	1		4			5	1