Ammonium ferric citrate (also known as Ferric Ammonium Citrate or Ammoniacal ferrous citrate) has the formula (NH₄)₅ e(C₆H₄O₇)₂ A distinguishing feature of this compound is that it is very soluble in water, in contrast to ferric citrate which is not very soluble. In its crystal structure each

moiety Moiety may refer to: Chemistry * Moiety (chemistry), a part or functional group of a molecule ** Moiety conservation, conservation of a subgroup in a chemical species Anthropology * Moiety (kinship), either of two groups into which a society is ...

citric acid Citric acid is an organic compound with the chemical formula HOC(CO2H)(CH2CO2H)2. It is a colorless weak organic acid. It occurs naturally in citrus fruits. In biochemistry, it is an intermediate in the citric acid cycle, which occurs in ...

has lost four protons. The deprotonated hydroxyl group and two of the carboxylate groups ligate to the ferric center, while the third carboxylate group coordinates with the ammonium.

Uses

Ammonium ferric citrate has a range of uses, including: * As a food ingredient, it has an INS number 381, and is used as an acidity regulator. Most notably used in the Scottish beverage

Irn-Bru Irn-Bru ( "iron brew", ) is a Scottish carbonated soft drink, often described as "Scotland's other national drink" (after whisky). Introduced in 1901, the drink is produced in Westfield, Cumbernauld, North Lanarkshire, by A.G. Barr of Glasgo ...

. * Water purification * As a reducing agent of metal salts of low activity like gold and

silver Silver is a chemical element with the symbol Ag (from the Latin ', derived from the Proto-Indo-European ''h₂erǵ'': "shiny" or "white") and atomic number 47. A soft, white, lustrous transition metal, it exhibits the highest electrical ...

* With

potassium ferricyanide Potassium ferricyanide is the chemical compound with the formula K3 e(CN)6 This bright red salt contains the octahedrally coordinated 3−.html" ;"title="e(CN)6sup>3−">e(CN)6sup>3− ion. It is soluble in water and its solution shows some g ...

as part of the

cyanotype The cyanotype (from Ancient Greek κυάνεος - ''kuáneos'', “dark blue” + τύπος - ''túpos'', “mark, impression, type”) is a slow-reacting, economical photographic printing formulation sensitive to a limited near ultraviolet ...

photographic process * Used in Kligler's Iron Agar (KIA) test to identify enterobacteriaceae bacteria by observing their metabolism of different sugars, producing hydrogen sulfide * In medical imaging, ammonium ferric citrate is used as a

contrast medium A contrast agent (or contrast medium) is a substance used to increase the contrast of structures or fluids within the body in medical imaging. Contrast agents absorb or alter external electromagnetism or ultrasound, which is different from radio ...

. * As a

hematinic A hematinic is a nutrient required for the formation of blood cells in the process of hematopoiesis. The main hematinics are iron, B12, and folate. Deficiency in hematinics can lead to anaemia. In cases of hematinic deficiency, hematinics can be ...

References

{{DEFAULTSORT:Ammonium Ferric Citrate Ammonium compounds Citrates Iron(III) compounds MRI contrast agents Photographic chemicals Double salts

Uses

See also

References