Ethylenediaminetetraacetic add EDTA

Two examples of polycarbonyl and polyamino compounds are shown in Figure 5.7. Ethylenediaminetetraacetic add (EDTA) is a synthetic ligand. The other, a siderophore, is biologically derived. Other polycyclic structures that coordinate with iron are also common. 

Iron is released from horse spleen ferritin by both 5-aminolaevulinic acid-generated 02 " and enoyl radical, which amplifies the chain of 5-aminolaevulinic acid oxidation (Rocha et al. 2000). Iron chelators such as ethylenediaminetetraacetic add (EDTA), ATP, but not dtrate, and phosphate accelerate this process and 5-aminolaevulinic acid-promoted iron release from horse spleen ferritin is faster in horse spleen isoferritins containing larger amounts of phosphate in the core. 

Blood Blood is taken from the vein without stasis. Additions of oxalate, fluoride, heparin, or ethylenediaminetetraacetic acid (EDTA) are without effect. Add 3 ml blood to 6 ml ice-cold perchloric acid, mix thoroughly and centrifuge for 15 min at 1000 xg. To 3 ml of the supernatant add 1 ml of potassium carbonate solution. After 15 min in an ice-bath, filter off the precipitate. Use the resultant solution for assay at room temperature. The content of fructose in blood is stable for 24 h when stored at 4°C. 

NTA = nitrilotriacetic acid, HEDTA = hydroxy-2-ethytenediaminetriacetic acid, CyDTA = trans-1,2-diaminocyclohexane-jV, A1, N, jV -tetraacetic acid, DTPA - diethylenetriaminepentaacetic add, EGTA = ethyleneglycolbis(2-aminoethyl)-Ar,Ar -tetraacetic add, EDTA = ethylenediaminetetraacetic acid, TTHA = triethylenetetraminetetraacetic add, PIDA = jV-(2-pyridylmethyl)iminodiacetic add, CyDA = cydohexyiiminodiacetic add. 

These compounds are neutral acids and have the structure (4). The list of the substances already investigated comprises the terms for n = 2 (ethylenediaminetetraacetic acid, edta),11 n = 3 (trimeth-ylenediaminetetraacetic add, tmta),12 n = 4 (tetramethylenediaminetetraacetic acid, teta),13 n = 5 (pentamethylenediaminetetraacetic acid, peta),14 n = 6 (hexamethylenediaminetetraacetic acid, hdta) and = 8 (octamethylenediaminetetraacetic acid, odta).14... 

The most important ferrous developers, however, are the complexes with ethylenediaminetetraacetic acid (EDTA) and related ligands, such as diethylenetriaminepentaacetic add (DTPA), nitrilotriacetic add (NT A) and JV-hydroxyethylethylenediaminetriacetic add (HETA). Complexes... 

An alternative technique for preventing the analyte forming refractory compounds in the flame is to add a compound to the sample which forms a preferential complex with the analyte. Ethylenediaminetetraacetic acid (EDTA) is often used since it complexes with the cation thus preventing its association with an anion that can lead to the formation of a refractory compound. 

Abbreviations BSA bovine serum albumin HSA, human serum albumin EDTA, ethylenediaminetetraacetic add DMSO, dimethylsulfoxide PEG, polyethylene glycol. 

Certain metals have a profound influence on the activity of the enzyme. Copper in concentrations as low as those resulting from contamination of glassware and reagents will catalyze nonenzymatic oxidation of p-phenyl-enediamine. For this reason it was recommended that 10 M EDTA (ethylenediaminetetraacetic acid) be incorporated in the reaction mixture (B28). However, higher concentrations of EDTA inhibit the enzyme, and it has been suggested that EDTA may form a complex with copper in ceruloplasmin and thereby inactivate the enzyme (H20, K3). The addition of EDTA to the reaction mixture therefore may not be desirable. We found that by simply avoiding copper contamination, by the use of precautions necessary in copper determinations, the nonenzymatic oxidation of p-phenylenediamine slows to an imperceptibly low rate, and in this situation there is of course no need to add EDTA. 

Abbreviations DHG = A,A-di(2-hydroxyethyl)glycine NTA = nitrilotriacetic add EDTA = ethylenediaminetetraacetic acid tiron = pyrocatechol-3,5-disulfonic add BAL = 2,3-dimercaptopropanol unithiol = sodium 2,3-dimercaptopropane sulfonate tren triaminatriethylamine penten = tetrakis(aminoethyl)ethylenediamine bipy = 2,2 -bipyridyl phen = 1, 10-phenanthroline. 

Lysis buffer. 10 mM triethanolamine-HCl of pH 8, 150 mM NaCl, 1 uM ethylenediaminetetraacetic acid (EDTA), 10% glycerol, 2% digitonin. Store at -20°C and add the 2% digitonin solution just before use. 

Stabilizers. All methacrylate monomers must contain some free-radical inhibitor if they are to be shipped and stored safely. Hydroquinone and p-methoxyphenol are most commonly used for this purpose. Most formulations will also contain benzoquinone, naphthoquinone, and similar stabilizers. Since the anaerobic compositions are strongly catalyzed by traces of metals, many formulators have found it advantageous to add chelators such as tetrasodium ethylenediaminetetraacetic acid (EDTA) (V). 

Heavy-metal poisoning is treated by administering chelating agents—substances that combine with the metal ions and hold them very tightly. One effective antidote is the chelating agent ethylenediaminetetraacetic add, or EDTA, which will chelate all heavy metals except mercury. 

Add leaching also allows mesopores to be created by a quite similar mechanism, that is, through the extraction of some aluminum from the framework positions. A typical procedure is slurrying the zeolite in a solution of ethylenediaminetetraacetic acid (EDTA) under reflux conditions for 18h [150]. Afterwards, the zeolite is heated under an inert gas at 1073 K. However, this method has the drawback of preferentially removing the external surface aluminum, leading to a nonuniform composition. 

N EDTA/0.2 N TRIS Solution Transfer 18.6 g of disodium ethylenediaminetetraacetate (EDTA) and 6.05 g of tris (hydroxymethyl)aminomethane (TRIS), both accurately weighed, into a 250-mL beaker. Add 200 mL of hot, deionized water, and stir until dissolved. Adjust the pH to 7.5 to 7.6 by adding 5 N sodium hydroxide. Cool the solution, and adjust the pH to 8.0 with 5 N sodium hydroxide. Transfer the solution into a 250-mL volumetric flask, and dilute to volume with deionized water. Mix well, and store in a plastic container. 

Despite the advances made with the Rev 2 formulation, reliability aspects, such as orifice plate cleanliness, and kogation, are still poor. To address the orifice plate cleanliness issue, we add 0.1 % of Zonyl FSA (an anionic fluorosurfactant from DuPont), following what has been done in the patent hterature. Furthermore, we add the combination of 0.3% Phospholan 9NP (a nonylphenol ethoxylate phosphate ester, from Akzo Nobel corporation), and 0.05% EDTA (ethylenediaminetetraacetic acid), to prevent resistor deposits, as discussed in the patent literature. With such modifications, the Rev 3 ink gives improved orifice plate cleanliness and kogation. The surface tension is lower for this formulation. Though this can lead to bleed problems on paper, here we have specified that the color inks will be at low pH, hence wiU react with the black pigment, and thus combating bleed problems. Furthermore excessive tail/aerosol formation may become a problem with the decreased surface tension, as mentioned back in Section 1.2 — this performance must be checked. 

M EDTA (disodium ethylenediaminetetraacetic acid) Weigh out an appropriate amount of EDTA and add to stirring distilled water (about 75% of the final volume). Add sodium hydroxide pellets slowly until the solution begins to clear. Monitor the pH and add NaOH until the EDTA has dissolved and the pH reaches between 7 and 8. Make up to the final volume, filter through a paper filter, and autoclave. Store the solution in a refrigerator. 

---