Ferric Pyrophosphate

The formula of calcium pyrophosphate is Ca2P207. Determine the formulas of sodium pyrophosphate and iron(III) pyrophosphate (ferric pyrophosphate). 

Ferric Pyrophosphate occurs as a tan or yellow-white powder. It is insoluble in water, but is soluble in mineral acids. 

Ferric pyrophosphate, Fe4(P207)3.9H20, is obtained as a white precipitate on adding ferric chloride solution to an equivalent amount of sodium pyrophosphate.6 It is soluble in ferric chloride, in excess of sodium pyrophosphate, and also in acids. 

Hydrogen ferri-pyrophosphate, H6[Fe2(P207)3].7H20, results as a white solid when ferric pyrophosphate is heated for twelve hours at 50° C. with syrupy pyrophosphoric acid in acetone. 

Iron deficiency anemia occurs mainly in infants, children, and fertile women. For this reason, a variety of foods, including infant formula and infant cereals, is fortified with iron. Ferrous sulfate is a form of iron that is most readily absorbed by the gut, but when added to dry cereals it can promote their spoilage and rancidity. For this reason, dry cereals are fortified with elemental iron particles, ferric pyrophosphate, or ferrous fumarate (Davidsson et ah, 1997). Ascorbic add may also be added to the cereal to enhance iron absorption. To view some of the numbers, infant cereals may contain 75 mg iron/kg cereal (1.3 mmol iron/kg), 1 mmol phytic acid/kg, and 2.6 mmol ascorbic acid/kg (Davidsson et cd., 1997). Although phytic acid impairs iron absorption, the added ascorbate serves to prevent this effect. An alternate method for preventing phytate from impairing iron absorption is to treat the food with the enzyme phytase. A parent interested in enhancing a child s iron absorption can easily feed a child some orange juice, but it would not be practical to pretreat the child s cereal with phytase. A typical availability of ferrous sulfate in infants is about 3-5% (with no ascorbate), and 6-10% (with ascorbate). Ascorbate is effective when present in a twofold molar excess over the iron. 

Properties Yellowish-white powder. Insoluble in water soluble in dilute acid. Contains 24% iron min, not to be confused with ferric pyrophosphate, soluble. 

Canned liquid soy-isolate infant formula Ferric pyrophosphate Ferric sodium pyrophosphate... 

Baked yeast-leavened rolls Sodium ferric pyrophosphate Ferric ortho phosphate FeS04... 

Processed (heat, enzyme, air-dry) mixed grain infant cereal Reduced iron Ferric ortho phosphate, or Sodium ferric pyrophosphate enriched cereals FeS04 enriched cereal Less Extrinsic (rat) 22... 

A number of investigators have studied the relative bioavailability of iron from various compounds that contained both iron and phosphorus. Three such salts that have been studied extensively are ferric phosphate, ferric pyrophosphate, and sodium-iron pyrophosphate. All three have been listed as Generally Recognized as Safe (GRAS) in the Code of Federal Regulations and have been added to foods in the United States as iron supplements (1). However, only small amounts of two of these phosphorus-containing salts, ferric pyrophosphate and sodium iron... 

This does not mean that the bioavailability of iron from all compounds containing both phosphorus and iron is low. Wood, et al. (12) and Theuer and his associates (7, 8) have found that the bioavailability of iron from sodium iron pyrophosphate and ferric pyrophosphate was greatly improved when the foods containing these salts were processed with heat and pressure (Table II). Such processing did not, however, improve the bioavailability of iron from ferric orthophosphate or ferrous sulfate. The reason for this effect is not known but sugars in the foods may have formed chelates with the iron that facilitated absorption. 

Ferric Pyrophosphate — ferric compound by sotlium pyrophosphate ... 

The ferri pyrophosphoH V. S.) is probably a mixture, or compound ( ) of ferric pyrophosphate, trisodic citrate, and ferric citrate. 

Ferric Sodium Pyrophosphate. Sodium ferric pyrophosphate. Fe4Na4O3SPl0. Hydrate Na(Fe4(P201).xH20. The commercial product contains 15.5-16.5% Fe and 50.5-52.5% PjOj,... 

Ferric Pyrophosphate—(Fej)a(Pa07)s—745.6—is precipitated by decomposition of a solution of a ferric compound by sodium pyrophosphate an excess of the Na salt dissolves the precipitate when warmed, and, on evaporation, leaves scales of a double salt, (Fea)j(PaOT)3, Na8(Pj07)a -I- 20 Aq. 

Ferric (III) phosphate. See Ferric phosphate Ferric pyrophosphate... 

Synonyms Iron (III) sodium pyrophosphate Sodium ferric pyrophosphate Sodium iron pyrophosphate... 

Sodium ferric pyrophosphate. See Ferric sodium pyrophosphate Sodium ferrocyanide CAS 13601-19-9 14434-22-1 (decahydrate) EINECS/ELINCS 237-081-9 INS535... 

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