Methyl violet is a family of that are mainly used as . Depending on the number of attached methyl groups, the color of the dye can be altered. Its main use is as a purple dye for textiles and to give deep violet colors in paint and ink. It is also used as a hydration indicator for silica gel. Crystal violet is also known as crystal violet (and many other names) and has medical uses.
Structure
The term methyl violet encompasses three compounds that differ in the number of methyl groups attached to the
amine functional group. Methyl violets are mixtures of tetramethyl (2B), pentamethyl (6B) and hexamethyl (10B) pararosanilins.
They are all soluble in water, ethanol, diethylene glycol and dipropylene glycol.
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Methyl violet 2B
Methyl violet 2B (IUPAC name: 4,4′-((4-Iminocyclohexa-2,5-dien-1-ylidene)methylene)bis( N, N-dimethylaniline) monohydrochloride) is a green powder which is soluble in water and ethanol but not in xylene. It appears yellow in solution of low pH (approximately 0.15) and changes to violet with pH increasing toward 3.2.
Methyl violet 10B
Methyl violet 10B has six methyl groups. It is known in medicine as Gentian violet (or crystal violet or pyoctanin(e)[ Kristallviolett – ein pH-Indikator ]
Methyl violet 10B inhibits the growth of many Gram positive bacteria, except streptococci. When used in conjunction with nalidixic acid (which destroys gram-negative bacteria), it can be used to isolate the streptococci bacteria for the diagnosis of an infection.
Degradation
Methyl violet is a mutagen and mitotic poison, therefore concerns exist regarding the ecological impact of the release of methyl violet into the environment. Methyl violet has been used in vast quantities for textile and paper dyeing, and 15% of such dyes produced worldwide are released to environment in wastewater. Numerous methods have been developed to treat methyl violet pollution. The three most prominent are chemical bleaching, biodegradation, and photodegradation.
Chemical bleaching
Chemical bleaching is achieved by oxidation or redox. Oxidation can destroy the dye completely, e.g. through the use of sodium hypochlorite (NaClO, common bleach) or hydrogen peroxide.[XP-Chloro Degradation Malachite green ] Reduction of methyl violet occurs in microorganisms but can be attained chemically using sodium dithionite.
Biodegradation
Biodegradation has been well investigated because of its relevance to sewage plants with specialized microorganisms. Two microorganisms that have been studied in depth are the white rot fungus and the bacterium Nocardia corallina.[
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Photodegradation
Light alone does not rapidly degrade methyl violet,
Other methods
Many other methods have been developed to treat the contamination of dyes in a solution, including electrochemical degradation,
See also
