Top Qs
Timeline
Chat
Perspective
Rhodamine B
Chemical compound From Wikipedia, the free encyclopedia
Remove ads
Rhodamine B /ˈroʊdəmiːn/ is a chemical compound and a dye. It is often used as a tracer dye within water to determine the rate and direction of flow and transport. Rhodamine dyes fluoresce and can thus be detected easily and inexpensively with fluorometers.
Rhodamine B is used in biology as a staining fluorescent dye, sometimes in combination with auramine O, as the auramine-rhodamine stain to demonstrate acid-fast organisms, notably Mycobacterium. Rhodamine dyes are also used extensively in biotechnology applications such as fluorescence microscopy, flow cytometry, fluorescence correlation spectroscopy and ELISA.[citation needed]
Remove ads
Other uses

Rhodamine B is often mixed with herbicides to show where they have been used.[3]
It is also being tested for use as a biomarker in oral rabies vaccines for wildlife, such as raccoons, to identify animals that have eaten a vaccine bait. The rhodamine is incorporated into the animal's whiskers and teeth.[4] Rhodamine B is an important hydrophilic xanthene dye well known for its stability and is widely used in the textile industry, leather, paper printing, paint, coloured glass and plastic industries.[5]
Rhodamine B (BV10) is mixed with quinacridone magenta (PR122) to make the bright pink watercolor known as Opera Rose.[6]
Remove ads
Properties

Rhodamine B can exist in equilibrium between two forms: an "open"/fluorescent form and a "closed"/nonfluorescent spirolactone form. The "open" form dominates in acidic condition while the "closed" form is colorless in basic condition.[7]
The fluorescence intensity of rhodamine B will decrease as temperature increases.[8]
The solubility of rhodamine B in water varies by manufacturer, and has been reported as 8 g/L and ~15 g/L,[2] while solubility in alcohol (presumably ethanol) has been reported as 15 g/L.[nt 1] Chlorinated tap water decomposes rhodamine B. Rhodamine B solutions adsorb to plastics and should be kept in glass.[9] Rhodamine B is tunable around 610 nm when used as a laser dye.[10] Its luminescence quantum yield is 0.65 in basic ethanol,[11] 0.49 in ethanol,[12] 1.0,[13] and 0.68 in 94% ethanol.[14] The fluorescence yield is temperature dependent;[15] the compound is fluxional in that its excitability is in thermal equilibrium at room temperature.[16]
Remove ads
Safety and health
In California, rhodamine B is suspected to be carcinogenic and thus products containing it must contain a warning on its label.[17] Cases of economically motivated adulteration, where it has been illegally used to impart a red color to chili powder, have come to the attention of food safety regulators.[18]
See also
References
Notes
Wikiwand - on
Seamless Wikipedia browsing. On steroids.
Remove ads