Ferrous acid citrate

Investigations in our laboratory corroborate Arrington s assertion that the complex that precipitates is the ferrous acid citrate species. The species that exist in solution as a function pH are shown in Figure 4. An insoluble FeHCit forms in the pH range of about 3.0 to 4.0. Raising the pH to >4 with either ammonia or sodium hydroxide eliminates this precipitate. 

To 10 ml of the injection add 20 mg of sodium metabisulphite, 0 1 ml of freshly-prepared ferrous sulphate-citrate solution and 1 ml of the buffer reagent. Mix, allow to stand for ten minutes and extract with 10 ml of ether. Reject the ether after separation and measure the extinction at 540 m/i. Calculate the adrenaline content by reference to a curve prepared by treating suitable quantities of a standard solution of adrenaline acid tartrate by the same process. 

Theory The limit test for Iron is based on the reaction between iron and thioglycollic acid in a medium buffered with ammonium citrate to give a purple colour, which is subsequently compared with the standard colour obtained with a known amount of iron (0.04 mg of Fe). Ferrous thioglycollate is a co-ordination compound that attributes the purple colour besides thioglycollic acid converts the entire Fe3+ into Fe2+. The reactions involved may be expressed as follows ... 

Oxalate is found to be a frequent impurity in pharmaceutical substances belonging to the category of either organic acids e.g.. anhydrous citric acid, tartaric acid or salts of organic acids e.g., ferrous gluconate, sodium citrate, potassium citrate and sodium cromoglycate. The presence of this impurity is due to the following two prime factors, namely ... 

Synonym Ammonia Water Amfbnioformaldehyde Ammonium Acetate Ammonium Acid Fluoride Ammonium Amidosulfonate Ammonium Amidosulphate Ammonium Benzoate Ammonium Bicarbonate Ammonium Bichromate Ammonium Bifluoride Ammonium Carbonate Ammonium Chloride Ammonium Citrate Ammonium Citrate, Dibasic Ammonium Decaborate Octahydrate Ammonium Dichromate Ammonium Disulfate-Nickelate (II) Ammonium Ferric Citrate Ammonium Ferric Oxalate Trihydrate Ammonium Ferrous Sulfate Ammonium Fluoride Ammonium Fluosilicate Ammonium Formate Ammonium Gluconate Ammonium Hydrogen Carbonate Ammonium Hydrogen Fluoride Ammonium Hydrogen Sulfide Solution Ammonium Hydroxide Ammonium Hypo Ammonium Hyposulfite Ammonium Iodide Ammonium Iron Sulfate Ammonium Lactate Ammonium Lactate Syrup Ammonium Lauryl Sulfate Ammonium Molybdate Ammonium Muriate Ammonium Nickel Sulfate Ammonium Nitrate Ammonium Nitrate-Urea Solution Ammonium Oleate... 

Absorption of iron by the individual varies with age, iron status, the amount and chemical form of the iron ingested, and with conditions in the gastrointestinal tract, only about 5—15% of iron in the diet being normally absorbed. Ferrous iron, as the sulphate, gluconate, fumarate or lactate or as ferrous ammonium sulphate, is appreciably taken up into the bloodstream from the duodenum, especially in the presence of ascorbic acid, a reducing agent. Little difference was found in the extent of their absorption between ferrous sulphate and the various chelates, but ferric ammonium citrate or polysaccharide complexes were only very poorly absorbed22)... 

Cellulose acetate phthalate is incompatible with ferrous sulfate, ferric chloride, silver nitrate, sodium citrate, aluminum sulfate, calcium chloride, mercuric chloride, barium nitrate, basic lead acetate, and strong oxidizing agents such as strong alkalis and acids. 

Ammonium ferric citrate, brown, soluble ferric citrate Contains about 9% NH, 16.5-18.5% Fe, and about 65% hydrated citric acid. Reddish-brown granules, garnet-red transparent scales, or brownish-yellow powder. Odorless or slight NHj odor saline, ferruginous taste. Very deliquesc. Reduced to ferrous salt by light. Extremely sol in water practically insol in alcohol. Keep well closed and protected from light... 

Ammonium ferric citrate, green. Contains about 7.5% NHj, 14.5-16% Fe, and about 75% hydrated citric acid. Green transparent, deliquesc scales, pearls, granules, or powder. Odorless mild ferruginous taste. More readily reduced to the ferrous salt hy light than the brown form. Very sol in water practically insol in ale. Keep well closed and protected from light. 

Ferrous Citrate, Several forms o( this salt are known. Prepn from citric acid and Fe powder Oroshnik, Haffcke, U,S. pat. 2,904,573 (1959 to Ortho) and ferrous salts Carlson, LI.S. pet. 3,091,626 (1963 to Scherer). 

Colorless, slightly acid liq. d about 1.00. Foams in the mouth, Keep protected from light and in a cool place. In-compat Alkalies, ammonia and their carbonates, albumin, balsam Peru, phenol, charcoal, chlorides, alkali citrates ferrous, mercurous or gold salts hypophosphites, iodides, lime water, permanganates, sulfites, tinctures, and organic matter in general. 

Cephalins Ethyl oleate Ferrous citrate L-Glutamic acid L-Histidine Iodine L-lsoleucine... 

Ferric pyrophosphate Ferric sodium pyrophosphate Ferrous fumarate Ferrous gluconate Ferrous gluconate dihydrate Ferrous lactate Ferrous sulfate anhydrous Ferrous sulfate heptahydrate Ferrous sulfate monohydrate Fumaric acid D-Gluconic acid Glucose L-Glutamic acid hydrochloride L-Glutamine Glycine Histidine hydrochloride monohydrate L-Histidine Inositol Iron Iron ammonium citrate... 

Calcium carbide Calcium cyanamide Di-iron phosphide Magnesium iron oxide removal Citric acid iron processing Bismuth iron refining Calcium cyanamide iron removal Aluminum sulfate iron source Sodium ferric EDTA iron source, food Ferrous fumarate iron source, infant formulas Ferrous fumarate iron source, nutritional food Ferric pyrophosphate iron source, nutritional infant formulas Ferric pyrophosphate iron source, nutritional pharmaceuticals Ferric pyrophosphate iron source, pharmaceuticals Ferrous fumarate iron source, special dietary food Ferric choline citrate iron, tempering Potassium ferricyanide iron/manganese removal, water treatment Calcium hydroxide iron/steel casting Tellurium... 

Synthesis of haem is readily accomplished from simple precursors. In the first step of porphyrin synthesis succinyl-CoA, which is produced in the citrate cycle and during the metabolism of various amino acids, is condensed with glycine to give d-aminolaevulinic acid, and it is this reaction which is rate-controlling. Subsequently two molecules of d-aminolaevulinic acid condense to form porphobilinogen and four molecules of porphobilinogen undergo a series of reactions to produce protoporphyrin which combines with ferrous ions to form haem. 

Morris speculated that the precipitate was a ferrous [Fe(ll)] salt. Hamm et al. identified three Fe(ll) complexes in aqueous solutions of citric acid and ferrous iron FeHCit, FeCit, and FeOHCit. Because FeHCit is the only identified uncharged species, the precipitate probably contained this compound. The aqueous chemistry of ferric/citric acid is more complex than the ferrous chemistry. The known Fe(lll) complexes include FeHCit, FeCit FeOHCit, and Fe(OH)2Cit. In addition, Bobtelsky and Jordan identified additional iron complexes (such as Fe2Cit3) in solutions containing sodium citrate and Fe(lli). These authors also offer evidence that hydrated species may be present. One composition that solved the iron precipitate problem was patented by Reich. He made mixtures of citric acid with formic acid that did not produce precipitates during the removal of mill scale from steel pipes. 

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