purpurin

In biochemistry, purpurin is a protein, belonging to the lipocalin family of proteins.

Madder Lake contains two organic red dyes: alizarin and purpurin.

Alizarin was discovered before Purpurin, by heating the ground madder with acid and potash.

Purpurin or purpurine may refer to:

Purpurin fluoresces yellow to red under UV light, while synthetic alizarin slightly shows violet.

A study in published in Nature suggests that the purpurin could replace cobalt in lithium-ion batteries.

They then found that Madder Lake contained two colorants, the red alizarin and the more rapidly fading purpurin.

Purpurin occurs in the roots of the madder plant (Rubia tinctorum), together with alizarin (1,2-dihydroxyanthraquinone).

Extracting purpurin from farmed madder is a simple task; alternately, the chemical could be synthesized in a lab.

Unlike alizarin, purpurin is dissolved by boiling in a solution of aluminum sulfate, from which it can be precipitated by acid.

Purpurin and alizarin were isolated from the root by Pierre Robiquet and Colin, two French chemists, in 1826.

Purpurin's Chemical Composition: 1,2,4 trihydroxyanthraquinone (C14H8O5)

Purpurin artifacts are frequently found during archeological excavations of more affluent Roman settlements, often along with actual Roman glass; Pompeii is a prime example.

Xanthopurpurin occurs in small amounts (as a glycoside) in the root of the common madder plant, Rubia tinctorum, together with alizarin, purpurin and other anthraquinone derivatives.

By drying, fermenting or a treatment with acids, this is changed to sugar, alizarin and purpurin, which were first isolated by the French chemist Pierre Jean Robiquet in 1826.

They also synthesized alizarin from bromoanthraquinone, which, together with the conversion of alizarin into purpurin published previously by M. F. De Lalande, provided the first synthetic route to purpurin.

Robiquet obtained from madder root two distinct molecules with dye properties, the one producing a magnificent red, that he called alizarin, which proved as well extremely stable, and another, of less stable properties, that he called purpurin.

Copper-based "red goldstone" aventurine glass exists on a structural continuum with transparent red copper ruby glass and opaque "sealing wax" purpurin glass, all of which are striking glasses, the reddish colors of which are created by colloidal copper.

Together with Carl Theodore Liebermann, he synthesized the orange-red dye alizarin in 1868; alizarin had been isolated and identified from madder root some forty years earlier in 1826 by the French chemist Pierre Robiquet, simultaneously with purpurin, a violet dye.

In the early 20th century, the U.S. National Association of Confectioners permitted mauveine as a food coloring with a variety of equivalent names: rosolan, violet paste, chrome violet, anilin violet, anilin purple, Perkin's violet, indisin, phenamin, purpurin, tyralin, Tyrian purple, and lydin.