Essential Ethylenediaminetetraacetic acid

Magnesium ions are essential for superprecipitation. This is borne out by the fact that an excess of EDTA (ethylenediaminetetraacetic acid) leads to complete inhibition. Another powerful inhibitor of superprecipitation is the sodium salt of o-[(3-hydroxymercuri-2-methoxypropyl)car-bamoyl]phenoxyacetic acid ( Salyrgan ). 

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%. 

Udenfriend et al developed a system for effecting aromatic hydroxylation consisting of ferrous sulfate, oxygen, ascorbic acid, and ethylenediaminetetraacetic acid (EDTA) in a phosphate buffer and noted that, in the cases tried, oxygen could be replaced by hydrogen peroxide in a nitrogen atmosphere. EOT A is not essential but greatly increases the reaction rate. Dihydroxymaleic acid and diethyl diketosuccinate were about as active as ascorbic acid alloxan and ninhydrin were less active. Examples ... 

Essential water Water in a solid that exists in a fixed amount, either within the molecular structure (water of constitution) or within the crystalline structure (water of crystalli-atioii). Ethylenediaminetetraacetic acid Probably the most versatile reagent for complex formation titrations forms chelates with most cations. See EDTA. 

Imanari et al. has reported a spectrophotometric detection of many inorganic anions using a post-column reactor [42]. A stream of ferric perchlorate, which is essentially colorless, is mixed with the column effluent. The ferric perchlorate is colorless because perchlorate is a poor complexing anion, but most anions will complex the iron and form colored species that can be detected at 330-340 nm (Table 4.3). A similar detection method works for ions such as orthophosphate, pyrophosphate, nitrilo-triacetic acid (NTA), and ethylenediaminetetraacetic acid (EDTA) [46]. 

Metal ion assisted electron transfer reactions are important when considering the roles of sequesterants and enzymes in antioxidant protection (8). Compounds like ethylenediaminetetraacetic acid (EDTA), phytic acid, and polyphenols can sequester transition metal ions and thereby inhibit oxidation. Binding the metal ions essentially prevents them from regenerating hydroxy radicals through the Fenton reaction. 

One of the major applications of pM buffers is in maintaining concentrations of necessary metal ions in biological nutrient media at essentially constant levels. As free metal ions are removed from the system, perhaps by hydrolysis or by incorporation into metalloenzymes, they are replenished by the reversible dissociation from a reservoir of metal complex. Among the first complexing agents used in this way were citrate and tartrate ions, but more recently aminopoly-carboxylic acids such as ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA) and nitrilotriacetic acid (NTA) have become the chelating agents... 

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