Auramine O is a diarylmethane
dye
A dye is a colored substance that chemically bonds to the substrate to which it is being applied. This distinguishes dyes from pigments which do not chemically bind to the material they color. Dye is generally applied in an aqueous solution an ...
used as a fluorescent
stain
A stain is a discoloration that can be clearly distinguished from the surface, material, or medium it is found upon. They are caused by the chemical or physical interaction of two dissimilar materials. Accidental staining may make materials app ...
. In its pure form, Auramine O appears as yellow needle crystals. It is insoluble in water and soluble in
ethanol and
DMSO.
Auramine O can be used to stain
acid-fast bacteria (e.g. ''
Mycobacterium
''Mycobacterium'' is a genus of over 190 species in the phylum Actinomycetota, assigned its own family, Mycobacteriaceae. This genus includes pathogens known to cause serious diseases in mammals, including tuberculosis ('' M. tuberculosis'') and ...
'', where it binds to the
mycolic acid in its cell wall) in a way similar to
Ziehl–Neelsen stain.
It can also be used as a fluorescent version of the
Schiff reagent.
Auramine O can be used together with
Rhodamine B as the Truant
auramine-rhodamine stain for ''
Mycobacterium tuberculosis
''Mycobacterium tuberculosis'' (M. tb) is a species of pathogenic bacteria in the family Mycobacteriaceae and the causative agent of tuberculosis. First discovered in 1882 by Robert Koch, ''M. tuberculosis'' has an unusual, waxy coating on its c ...
''.
It can be also used as an
antiseptic agent.
References
External links
Auramine O spectra data
{{Stains
Diarylmethane dyes
Staining dyes
Antiseptics