Sodium-EDTA chelate

A common form of EDTA used as a preservative is calcium disodium EDTA (CaNa2EDTA). What metals will this form of the sequestrant scavenge effectively The dissolution of the solid will yield calcium ions, sodium ions, and the EDTA anion. Any metal more effectively complexed than calcium will be readily scavenged, including all ions listed in Table 9.1 except silver (Ag+) and magnesium (Mg2+). (In the absence of the calcium counterion, as in the case of the acid form of EDTA, chelation of calcium in the body can occur. In fact, EDTA administered orally is an FDA-approved treatment for calcium deposits in the bloodstream that lead to cardiovascular disease.) Citric acid (Fig. 9.3.3) is another sequestrant of metal ions in foodstuffs. 

The mash from the Streptomyces aureofaciens fermentation broth is acidified and filtered. The filtrate is adjusted to the desired pH, usually 7-8.5, and various flocculating or chelating agents may be added (e.g., vinyl acetate-maleic anhydride copolymer, sodium EDTA, ammonium oxalate, Arquad). The precipitate is (1) stirred with filter aid, filtered, stirred with HC1, refiltered, mixed with 2-ethoxyethanol, filtered, washed, and the filtrates are combined, acidified with HC1, NaCl is added, and the crystals are collected, washed with 2-ethoxyethanol, water, and ethanol, and dried (67), or (2) extracted into methyl isobutyl ketone, the extracts are combined, filtered, and acidified with HC1, and the crystals are collected and washed with water, 2-ethoxyethanol, and isopropanol, and vacuum-dried. If the crystals are greenish, they are treated with sodium hydrosulfite at pH 1.8, filtered, washed, and dried as in (1) above (68). 

EDTA is marketed in its salt forms such as sodium EDTA or calcium EDTA. EDTA has industrial and medical uses as a chelating agent. Much of its utility is related to the fact that... 

EDTA chelation The EDTA chelation test evaluates the extent to which cationic metals (e.g., Al, Ba, Cd, Co, Cu) can be made less toxic or non-toxic by the addition of EDTA (Ethylenediaminetetraacetate). A cationic metal may be suspected as the cause of toxicity if both EDTA and sodium thiosulfate reduce toxicity. EDTA is typically added as a gradient of concentrations (based on its toxicity to the species of interest) to a single effluent concentration. 

Tetra sodium salt (Na4) of EDTA. Chelating agent for calcium, magnesium and other divalent and trivalent metal ions in acid, neutral and alkaline conditions. 

Questal. [Clough] Sodium EDTA or HEDTA chelating agents. 

Calmosine CCRIS 6795 Edathamil monosodium ferric salt EINECS 239-802-2 Feredalo sodico Feredetate de sodium Ferisan Ferric sodium edetate Ferric sodium EDTA Ferrostrane Ferrostrene Monosodium ferric EDTA Natrii feredetas NSC 5237 Sequestrene Na Fe iron chelate Sequestrene NaFe Sodium feredetate Sodium ferric EDTA Sodium iron EDTA Sodium ironedetate Sybron Sytron. Used as a source of iron, a hematinic. Crystals. 

EDTA (ethylenediaminetetraacetic acid) forms stable metal chelates with a number of metal ions. Using this reagent as a complexing- agent, arsenic, bismuth, and selenium can be determined without any interference in the presence of nickel and cobalt. The cobalt-EDTA chelate is stable in 5 M HCl solution, whereas the corresponding bismuth complex is not. The influence of copper on the determination of arsenic can also be eliminated with EDTA, but not in the determination of selenium. Thiourea has been used to eliminate the influence of copper in the determination of antimony and sodium oxalate to eliminate the influence of copper and nickel in the determination of tin. An addition of thiosemicarbazide and 1,10-phenanthro-line reduces the interference of copper, nickel, platinum, and palladium in the determination of arsenic. 

The calcium chelation value of a substance can be determined by an oxalate titration. In this method [12], a sample of the product to be tested is added to a sodium oxalate solution at pH 10 to 12. The mixture is then titrated with a solution containing calcium ions. When the chelate becomes depleted the endpoint can be noted by the precipitation of insoluble calcium oxalate. The calcium chelation value (CV) is reported as mg of calcium chelated per gram of chelate. The CV of Na LED3 A was determined at a range of concentrations. The results are presented in Figure 7. EDTA chelates 260 mg CaCOj/g irrespective of system concentration. 

EDTA (ethylenediaminetetraacetic acid, [60-00-4]) chelates any trace metals that would otherwise decompose the hydrogen peroxide [7722-84-1]. The amine is preheated to 55—65°C and the hydrogen peroxide is added over one hour with agitation the temperature is maintained between 60 —70°C. The reaction is exothermic and cooling must be appHed to maintain the temperature below 70°C. After all the peroxide has been added, the temperature of the reaction mixture is raised to 75°C and held there from three to four hours until the unreacted amine is less than 2.0%. The solution is cooled and the unreacted hydrogen peroxide can be destroyed by addition of a stoichiometric amount of sodium bisulfite. This may not be desirable if a low colored product is desired, ia which case residual amounts of hydrogen peroxide enhance long-term color stabiUty. 

Ethylenediamine tetraacetic acid (EDTA) [60-00-4] (Sequestrene), an anticoagulent at 1 mg of the disodium salt per mL blood, complexes with and removes calcium, Ca ", from the blood. Oxalate, citrate, and fluoride ions form insoluble salts with Ca " and chelate calcium from the blood. Salts containing these anticoagulants include lithium oxalate [553-91-3] 1 mg/mL blood sodium oxalate [62-76-0]2 mg/mL blood ... 

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