Iron citrate

Citrates. Iron citrate [2338-05-8] is a compound that contains citric acid and iron(II) and iron(III) in indefinite ratios. Iron(II) citrate [23383-11-1] and iron(III) citrate [28633-45-6] are also of indefinite stoichiometry, although iron(III) citrate which contains Fe and citric acid in a 1 1 ratio [3522-50-7] is known. These compounds dissolve slowly in water and are more readily soluble in hot water. The solution chemistry of these compounds is comphcated by formation of a number of monomeric and oligomeric species. All of the iron citrate compounds are used as supplements to soils and animal diets. 

Francis AJ, CJ Dodge (1993) Influence of complex structure on the biodegradation of iron-citrate complexes. Appl Environ Microbiol 59 109-113. 

Iron citrate, 74 533 Iron cobalt black spinel, formula and DCMA number, 7 348t... 

Iron(III) citrate, " " or iron(III) ammonium citrate, is the usual vehicle for administering supplementary iron to an iron-deficient patient, for inducing iron-overload in rats or other creatures prior to testing the efficacy of iron chelators, or for introducing the isotope Fe for metabolic tracer studies. Stability constants for the aqueous iron(III)-citrate system have been established. " The 2 1 complex is claimed to be the dominant species in iron(III)/citrate/DMF systems. " There has been a very qualitative study of the incorporation of iron into transferrin from iron citrate. " Iron(III) citrate reacts relatively slowly with the aluminum(III)-transferrin complex to give the thermodynamically strongly favored combination of iron(III)-transferrin with aluminum(lll) citrate. " The mechanism of iron uptake from citrate complexes in cells has been briefly discussed. An octa-iron citrate complex appears in Section 5.4.5.4.3 below. 

Iron citrate [2338-05-8] Iron-cobalt Iron-cobalt alloys... 

Much of the work on the identification of carboxylic add complexation has been pioneered by Tiffen. He was the first to positively identify an iron-citrate complex in plant xylem.22 Iron-dtrate complexes have since been identified in a number of plants. The complex formed in these plant fluids is anionic, and Tiffen has shown that a number of other metal ions (Cr, Cu, Ni, Mn and Zn) are also present as anionic complexes.23 Although the neutrality of complexes may be considered a prerequisite for metal ion penetration of membranes, this has not been demonstrated with plant roots or with leaf-cell membranes. Involvement of negatively charged dtrate complexes of Ni11 has been confirmed both for nickel uptake and for translocation in plant species.24 Trisoxalatochro-mate(III) anion has been found in the leaf tissues of a plant species.25... 

Synonyms Ammoniocitrate of iron, Ammonium citrate, Iron citrate, Soluble ferric citrate. Appearance Clear green crystals. Occurs also as brown scales, but green scales are preferred for photographic purposes. 

Catalyst preparation and inspection by microscopy. Preparation by impregnation with ammonium iron citrate and iron nitrate resulted in a homogeneous iron distribution as determined by light microscopy. Ammonium iron EDTA as a precursor yielded an eggshell distribution of the iron compound. Finely divided material deposited on the support was observed with Transmission Electron Microscopy in all catalysts. Tn addition to this, some material deposited next to the support was observed in catalysts ex nitrate. It was therefore decided to focus on the catalysts prepared with ammonium Fe(ITI) citrate. 

Iron(II) and iron(III) citrates are known but have a poorly defined composition, though octa-iron and nona-iron citrate complexes have been characterized in solution, complex species exist. Brown and green hydrated iron(III)... 

Also shown in Figure 8 is the absorption spectrum of the iron-citrate complex obtained by preparing 0.1 mM Fe + in the presence of 10 mM citrate. Figure 8 thus provides a rationale for why the UV and visible ICH stressing conditions will both lead to the observed photodegradation as Fe can be photoreduced to Fe + in the presence of citrate by either lamp output. 

Figure 8 Solid lines) Spectral outputs for International Conference on Harmonization (ICH) visible and ultraviolet lamps with Hg emission lines removed dotted line) absorption spectrum for the iron-citrate complex dashed line) transmission profile for the yellow light filters used in this study and common to many manufacturing areas. Note the spectral overlap of both ICH lamps with iron-citrate complex absorption.

Figure 12 Photocatalytic scheme for iron-citrate mediated generation ot Fe, which reacts with oxygen to form two equivalents of superoxide radicals for every photon absorbed.

Excess iron citrate reagent is added to the sample to saturate all available transferrin sites. After an incubation period of three to five minutes the treated specimen is applied to an alumina column where iron that is not bound to transferrin is absorbed. The transferrin-bound iron contained in the eluate is the total iron-binding capacity of the specimen. The total iron-binding capacity is determined with the slides for iron in the same manner as for an untreated serum specimen. (For details of the iron method, see pp. 197 fl). 

The role of melanotransferrin has been recently elucidated by Kennard et al. [207] who demonstrated that this membrane bound iron binding protein is involved in the transferrin-independent uptake of iron in mammals but from iron-citrate and not from iron-transferrin complexes. This alternative iron uptake pathway may not function in the normal recirculation of iron within the body but might play a role during iron overload. On the other hand, rapidly proliferative tumor cells like melanocytes could use the alternative pathway to increase iron uptake. This independent system could also participate in the absorption of iron by intestinal cells that have no transferrin receptor on their lumenal surfaces [208], but express a transferrin-like GPI-linked iron-binding protein at the apical surface of fetal intestinal epithelial cells [209]. 

Ferric citrate 4160 Fe2(C6Hj07)2 Citrate of iron citrate of sesquioxide of Iron prussiate of Iron. 

Syrup of Tannate of Iron. Citrate of iron, 2 drachms dissolved in 1 ounce diluted acetic acid, is added to 12 ounces sim-... 

Citric acid solnbilizes iron, forming soluble iron citrate. Citric acid is an anthorized additive at doses np to 0.5 g/1. The total concentration must never exceed 1 g/1. This treatment may only be envisaged for wines that have been sufficiently sulfured to protect them from bacterial activity that would otherwise break down the citric acid, producing volatile acidity. In practice, this treatment is used exclusively for white wines that are not very susceptible to ferric casse (with no more than 15 mg/1 of iron) and that will not be damaged by this acidification. Doses of 20-30 g/hl are usually sufficient. 

CAS 3522-50-7 (anhyd.) 2338-05-8 (monohydrate) 28633-45-6 EINECS/ELINCS 219-045-4 Synonyms Iron citrate Iron (III) citrate... 

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