Chelating agents EDTA ethylenediaminetetraacetic

Chelating agents edta ethylenediaminetetraacetic acid, edtaoh = hydroxyethylethylenediaminetriaceticacid, cydta = cyclohexanediaminetetraacetic acid, hdtpa = protonated diethylenetriaminepentaacetic acid, [Co(III)(en)2(PVP)Cl]Cl x ethyl 0.45, DP of PVP 98. 

Economics and Marketing. The fastest-growing end use of ethylenediamine is in the manufacture of the chelating agent EDTA (ethylenediaminetetraacetate), which is a product of the reaction of EDA with chloro-acetic acid or sodium cyanide/formaldehyde. Its average growth rate in the late 1980s was about 6 percent. 

The removal of thorium from the body has been achieved by the use of chelating agents, primarily ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DTPA) (Fried and... 

As an alternative to acid washing, soils can also be flushed with chelating agents. Examples of effective chelating agents include ethylenediaminetetraacetic acid (EDTA) and nitrilotriacetic acid (NTA), both of which readily bind and solubilize metals. Using this approach, Peters Shem (1992) have recently reported on the removal of lead from a contaminated soil. In this study, 0.1M EDTA removed 60% of the lead in a soil containing 10 000 mg lead/kg. 

The antioxidant synergists enhance the effect of antioxidants. Chelating agents like ethylenediaminetetraacetic acid (EDTA) are commonly added to parenterals. They may reduce oxidative damage by forming complexes with oxidative metal ion catalysts. Chelating agents are further discussed in Section 14.2.6. 

Certain compounds, known as chelating agents (qv), react synergisticaHy with many antioxidants. It is beheved that these compounds improve the functional abiUties of antioxidants by complexing the metal ions that often initiate free-radical formation. Citric acid and ethylenediaminetetraacetic acid [60-00-4] (EDTA), C2QH2gN20g, are the most common chelating agents used (22). 

The lanthanides form many compounds with organic ligands. Some of these compounds ate water-soluble, others oil-soluble. Water-soluble compounds have been used extensively for rare-earth separation by ion exchange (qv), for example, complexes form with citric acid, ethylenediaminetetraacetic acid (EDTA), and hydroxyethylethylenediaminetriacetic acid (HEEDTA) (see Chelating agents). The complex formation is pH-dependent. Oil-soluble compounds ate used extensively in the industrial separation of rate earths by tiquid—tiquid extraction. The preferred extractants ate catboxyhc acids, otganophosphoms acids and esters, and tetraaLkylammonium salts. 

Thennodynamic inhibitors are complexing and chelating agents, suitable for specific scales. For example, for scale inhibition of barium sulfate, common chemicals are ethylenediaminetetraacetic acid (EDTA) andnitrilotriacetic acid. The solubility of calcium carbonate can be influenced by varying the pH or the partial pressure of carbon dioxide (CO2). The solubility increases with decreasing pH and increasing partial pressure of CO2, and it decreases with temperature. 

The heavy metals copper, manganese, cobalt and zinc were omitted individually and in combination from MS and B5 media to determine the effect on antibody stability in solution [63]. When IgG, antibody was added to these modified media in experiments similar to the one represented in Figure 2.2, only the B5 medium without Mn showed a significant improvement in antibody retention relative to normal culture media. Nevertheless, protein losses were considerable as only about 30% of the added antibody could be detected in the Mn-free medium after about 5 h. The beneficial effect of removing Mn was lost when all four heavy metals, Cu, Mn, Co and Zn, were omitted simultaneously. The reason for these results is unclear. Addition of the metal chelating agent ethylenediaminetetraacetate (EDTA) had a negligible effect on antibody retention in both MS and B5 media [63]. 

A very important ligand (or chelating agent) for titrimetric analysis is the ethylenediaminetetraacetate (EDTA) ligand. It is especially useful in reacting with calcium and magnesium ions in hard water such that water hardness can be determined. The next section is devoted to this subject. 

Ethylenediaminetetraacetic acid (EDTA) is a chelating agent that binds certain metals, especially iron and copper, which are essential to the nutrition of certain microorganisms. In this manner, it is a strong booster or enhancer of the activity of preservatives especially the parabens. Alone, it has the ability to increase the permeability of the bacterial cell wall and can kill Pseudomonas aeruginosa and E. coli by this activity effective concentration is 0.05-0.10%. 

Ethylenediaminetetraacetic acid (EDTA), a chelating agent widely used by biochemists for... 

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