Chelating agents disodium edetate

Disodium edetate Chelating agent Sodium saccharin Sweetening agent... 

Chelating agents such as disodium edetate (EDTA) are commonly used in lens care products to enhance the antimicrobial activity of preservatives and remove calcium and magnesium from the lens. EDTA is the most... 

Disodium edetate is used as a chelating agent in a wide range of pharmaceutical preparations, including mouthwashes, ophthalmic preparations, and topical preparations, typically at concentrations between 0.005 and 0.1% w/v. 

Disodium edetate forms stable water-soluble complexes (chelates) with alkaline earth and heavy-metal ions. The chelated form has few of the properties of the free ion, and for this reason chelating agents are often described as removing ions from solution, a process known as sequestering. The stability of the metal-edetate complex is dependent on the metal ion involved and the pH. 

Edetic acid and edetate salts are used in pharmaceutical formulations, cosmetics, and foods as chelating agents. They form stable water-soluble complexes (chelates) with alkaline earth and heavy metal ions. The chelated form has few of the properties of the free ion, and for this reason chelating agents are often described as removing ions from solution this process is also called sequestering. The stability of the metal-edetate complex depends on the metal ion involved and also on the pH. The calcium chelate is relatively weak and will preferentially chelate heavy metals, such as iron, copper, and lead, with the release of calcium ions. For this reason, edetate calcium disodium is used therapeutically in cases of lead poisoning see also Section 18. 

Comments used in pharmaceutical formulations as a chelating agent in concentrations between 0.01-0.1% w/v. Usually edetate calcium disodium is used in pharmaceutical formulations in preference to disodium edetate or sodium edetate to prevent calcium depletion occurring in the body. In food products, edetate calcium disodium may also be used in flavors and as a color retention agent. Edetate calcium disodium occurs as the dihydrate, trihydrate, and anhydrous material. 

Comments more soluble in water than either the disodium salt or the free acid. Trisodium edetate also occurs as the monohydrate and is used in pharmaceutical formulations as a chelating agent. The EINECS number for trisodium edetate is 205-758-8. 

Oxidation reactions can be catalysed by the presence of tiny amounts of metal ions (for example, 0.05 ppm Cu2+ can initiate decomposition of fats) and so stainless steel or glass apparatus should be used wherever possible during manufacture of susceptible compounds. If the presence of metal ions cannot be avoided, then chelating agents, such as disodium edetate, are used to chelate and remove metal ions. Disodium edetate is the disodium salt of ethylenediaminetetraacetic acid, or EDTA, and is shown in Figure 8.12. 

Edetate sodium/ Edetate disodium Airet, Alupent, Atrovent Chelating agent 0.02%/0.03%... 

Edetate calcium disodium, a metal-chelating agent, is indicated in the treatment of symptomatic lead poisoning without encephalopathy and blood lead concentrations less than 100 mcg/dL, or in the treatment of severe lead poisoning with symptoms of encephalopathy and/or blood lead concentrations greater than 100 mcg/dL. 

EDTA, its sodium salt (edetate disodium, Na2EDTA), and a number of closely related compounds chelate many divalent and trivalent metals. The cation used to make a water-soluble salt of EDTA has an important role in the toxicity of the chelator. Na2EDTA causes hypocalcemic tetany. However, edetate calcium disodium (CaNa2EDTA) can be used for treatment of poisoning by metals that have higher affinity for the chelating agent than does Ca. ... 

Corneal band keratopathy Edetate disodium (disodium EDTA Endrate) is a chelating agent that can be used to remove a band keratopathy (i.e., a calcium deposit at the level of Bowman s membrane on the cornea). After the overlying corneal epithelium is removed, it is applied topically to chelate the calcium deposits from the cornea. 

Because the onset of lead poisoning usually is insidious, it often is desirable to estimate the body burden of lead in individuals who are exposed to an environment that is contaminated with the metal. In the past, the edetate calcium disodium (CaNaJlDTA) provocation test was used to determine whether there is an increased body burden of lead in those for whom exposure occurred much earlier. The provocation test is performed by intravenous administration of a single dose of CaNa DTA (50 mg/kg) followed by collection of urine for 8 hours. The test is positive for children when the lead excretion ratio (pg of lead excreted in the urine per mg of CaNa DTA administered) is >0.6 it also may be useful for therapeutic chelation in children with blood levels of 25 5 pg/dL. This test is not used in symptomatic patients or in those whose concentration of lead in blood is >45 pg/dL because these patients require the proper therapeutic regimen with chelating agents (see below). 

The health-care provider has prescribed edetate calcium disodium (Calcium EDTA), a chelating agent, for a child diagnosed with lead poisoning. Which intervention should the nurse implement ... 

A number of natural substances, including sodium citrate and ascorbic acid, chelate Pb. Commonly used chelating agents include calcium disodium edetate (CaEDTA), dimercaprol (BAL), 2,2-dimethylcysteine (D-peniciUamine) and 2,3-dimercaptosuc-cinic acid (DMS). Chisholm and Coffin et al." have outlined the appropriate protocols for chelation therapy for children wdth Pb poisoning, whereas Friedheim et al. and the Center for Disease Control, outline the treatment of adult Pb intoxication. 

Di-Na monO Ca salt [62-33-9]. Sodium calcium edetate, BAN, INN. Edetate calcium disodium, USAN. Edathamil calcium disodium. Calcium disodium versenate. Mosatil. Antallin. Ledclair. Other proprietary names Powerful chelating agent used for treatment of lead poisoning. Powder. Forms a tetrahydrate. 

Some strains of P. aeruginosa are resistant to benzalkonium chloride and, in fact, can be grown in solutions concentrated in this agent. This has caused great concern because of the virulent nature of this organism in ocular infections, as discussed previously. Thus, it was an important finding in 1958 that the acquired resistance could be eliminated by the presence of ethylenediaminetetracetic acid (sodium edetate) in the formulation. This action of EDTA has been correlated with its ability to chelate divalent cations, and it is commonly used as a preservative aid [125]. The use of disodium EDTA, where compatible, is recommended in concentrations up to 0.1%. 

Medical treatment with chelation uses four different agents British Anti-Lewisite (2,3-dimercaptopropanol), edetate calcium disodium, D-penicillamine, and succimer or meso-2,3-dimercaptosuccinic acid (Roper et al. 1993). British Anti-Lewisite is contraindicated in children allergic to peanuts and in glucose-6-phosphate dehydrogenase deficiency D-penicillamine is contraindicated in penicillin allergy (Roper et al. 1993). 

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