Ethylenediamine tetraacetic acid, additive

Hydrated lanthanide salts may also be obtained by the addition of an excess of lanthanide oxide to a concentrated acid solution, heating at 80°C until the pH is between 5 and 6. The residual oxide is removed by filtration, and the filtrate is subjected to rotary evaporation. This procedure may lead to the presence of oxo and hydroxy species in solution. At present hydrated lanthanide salts of 99.9% purity are available commercially. Salts of the highest purity are generally used in spectroscopic and magnetic studies. The purity of lanthanide salts can be determined by complexometric titration with ethylenediamine tetraacetic acid [1]. 

Both ethylenediamine tetraacetic acid (EDTA) and benzalkonium chloride used as stabilizing and bacteriostatic agents, respectively, can produce bronchoconstriction. In addition to producing bron-choconstriction, EDTA potentiates the bronchial responsiveness to histamine. These effects presumably are mediated through calcium chelation by EDTA. Benzalkonium chloride is more potent than EDTA, and its mechanism appears to be a result of mast cell degranulation and stimulation of irritant C fibers in the airways. ... 

External microdialysis probes fabricated in-house were used in these experiments. Initial studies found that the addition of ethylenediamine tetraacetic acid (EDTA) to the derivatizing reagent was necessary to prevent divalent cations (Mg + and Ca +) present in the cerebral spinal fluid from decreasing the EOE. Using the device, separations could be carried out at 1.8 min intervals however, the effective temporal resolution was estimated to be between 2 and 4 min due to delay times attributed to the dead volume in the system. Increases in perfusion flow rates led to a decreased delay time but reduced recovery through the probe was observed. 

Surfactants reduce electron transfer resistance across cell membranes. On addition of surfactants, the membrane permeability of electroactive bacteria was significantly increased, which in turn accelerated the electron shuttle transport across the cell membrane. Moreover, the surfactant changed the cell roughness and increased the cell adhesion on the solid electrode, which resulted in higher biofilm loading. For example, chemically synthesized surfactants ethylenediamine tetraacetic acid (EDTA), polyethyleneimine... 

Many metal ions (e.g., calcium, cadmium, aluminum, lead) can be titrated with standard ethylenediamine-tetraacetic acid (EDTA) or other compleximetric titrants, using an appropriate indicator electrode. When no direct appropriate indicator electrode exists, the addition of indicator metal ions can permit a determination. For example, barium may be titrated with EDTA in the presence of silver-EDTA complex as an indicator reagent using a silver electrode. Examples of compleximetric titrations are given in Table 3. 

Cobalt salts and oxides are used in the glass industry, for paints and colored pottery (10). They are also used as fodder additives for ruminants, as fertilizers, as catalysts in chemistry, as vitamin and radiation sources ( Co in medicine), as amalgam in dentistry, and as antidotes of cyanides in the form of ethylenediamine tetraacetic acid (EDTA) complexes. Several years ago, C0SO4, C0CI2, and Co(OAc)2 were used as foam stabilizers in the brewing of malt beverages. This is no longer allowed due to the cardiovascular diseases that were induced. 

Fig. 28 Left design strategy for Eu-based fluorescence nanoparticle sensor (EDTAD is ethylenediamine tetraacetic acid dianhydride). Right (a) fluorescence response of the sensor (Eu° content 10 pM) upon addition of different concentrations of CaDPA at pH 6.5, (b) fluorescence intensity at 616 nm of the sensor as a function of CaDPA concentration, (c) visual fluorescence colour changes of the sensor (Eu° content 120 pM) upon addition of different concentrations of CaDPA (from left to right 0, 25, 50, 100 pM). Adapted with permission from [135]...

Chelation with di- and trivalent metal ions showed even more drastic permeability changes. The experiment was performed by alternating addition of and ETA (ethylenediamine-tetraacetic acid disodium salt), an effective polydentate ligand for Cu. The result is shown in Fig. 25. It is seen that the alternating addition of Cu ... 

ATPE = addition de photons par transfert d energie EDTA = ethylenediamine tetraacetic acid EG = ethylene glycol ESA = excited state absorption ETU = energy transfer upconversion GSA = ground-state absorption HRTEM = high-resolution transmission electron microscopy ... 

Treatment of the neurotoxin with metal chelators such as ethylenediamine tetraacetic acid (EDTA) inactivate most (80%) of the enzymatic activity, and large part (80%) of the lost activity can be restored with the addition of Zn " ions activity (Foran et al., 1994). Similar loss of toxic activity of type A botulinum neurotoxin was recently observed in our studies with the neurotransmitter release studies in PC 12 cells (F. -N. Fu, R. Lomneth and B. R. Singh, unpublished data). However, the loss of activity was not restored with the replenishment with Zn " ions. The loss of activity at least in part seems to be caused by the change in the polypeptide folding (Fu and Singh, 1995). 

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