Heavy metal-EDTA chelates

CNC POLYQUEST 80 is a chemical compound which inactivates iron in peroxide bleach baths. In general, it complexes alkaline earth as well as heavy metals. It chelates these metals more strongly than EDTA Salts and is recommended for the inactivation of trace catalytic metals. 

In a separate study, Igwe and Abia46 determined the equilibrium adsorption isotherms of Cd(II), Pb(II), and Zn(II) ions and detoxification of wastewater using unmodified and ethylenediamine tetraacetic acid (EDTA)-modified maize husks as a biosorbent. This study established that maize husks are excellent adsorbents for the removal of these metal ions, with the amount of metal ions adsorbed increasing as the initial concentrations increased. The study further established that EDTA modification of maize husks enhances the adsorption capacity of maize husks, which is attributed to the chelating ability of EDTA. Therefore, this study demonstrates that maize husks, which are generally considered as biomass waste, may be used as adsorbents for heavy metal removal from wastewater streams from various industries and would therefore find application in various parts of the world where development is closely tied to affordable cost as well as environmental cleanliness.46... 

Koehler, F.M., Rossier, M., Waelle, M., Athanassiou, E.K., Limbach, L.K., Grass, R.N., Gunther, D. and Stark, W.J. (2009) Magnetic EDTA coupling heavy metal chelators to metal nanomagnets for rapid removal of cadmium, lead and copper from contaminated water. Chemical Communications, (32), 4862—4864. 

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]. 

EDTA salts are used for the treatment of heavy metal poisoning. Roosels and Vanderkeel142) were able to extract lead from urine in the presence of EDTA with dithizone by adding calcium to presumably release the lead from EDTA. In view of the fact that the formation constant of the lead-EDTA chelate is 20,000,000 times larger than that of the corresponding calcium chelate, it is doubtful that the calcium actually releases the EDTA from the lead. 

As heavy metals were known to influence the degradation pathway, experiments were carried ont to determine if excess levels of metals could be the root cause of the degradation. EDTA (ethylenediaminetetraacetic acid) is a known metal chelator and is often used in ampoule formulations. The addition of EDTA to samples of ampoule solutions prepared in the lab was shown to halt the degradation (Table 2). 

EDTA Chelators of cations, particularly heavy metals... 

Chelating agents are widely used as specific antidotes for heavy metals. They form stable, soluble, nontoxic complexes and in easily excreted form. They promote dissociation of bound metal from tissue enzymes and other functional macromolecules. These metal chelates are water soluble, e.g. EDTA, BAL, desferrioxamine etc. 

EDTA Chelates alkaline earth and heavy metals 0.005-0.01% w/v antimicrobial activity synergy Often used in combination with other antimicrobial preservatives, and other antioxidants based on their synergy... 

Chemical - complex formation. Earlier we discussed the complexation which can occur between the chelating agent EDTA and heavy metals or the sequestration of lipids in cholestyramine resins. The immune system has antibody-antigen complexes formed which can help in the elimination of the antigen (xenobiotic). 

The a-amino acids have been reported to form stable complexes with transition metals. The derivatives of acetic acid are particularly noteworthy for their chelating ability. The most remarkable for the acetic acid derivatives, however, is ethylenediamine tetraacetic acid (often abbreviated EDTA or H4Y). The complexes of EDTA are remarkably stable, and have been investigated extensively from the industrial point of view. The substance has been used in water softening, electroplating, controlling of metal content of dye paths, in removing lead and other heavy metals from the human systems, and in the treatment of chlorosis in plants [7]. 

Ethylenediaminetetracetic acid (EDTA), usually as the di-sodium salt, is added to a concentration of 1 mM to chelate heavy metal ions, which can inhibit enzymes at very low concentrations, and also to remove Ca2+ and Mg2+, which can otherwise act... 

Lead can accumulate in the bones and other body tissues unless removed soon after ingestion. In some cases, treatment with chelating agents such as EDTA has been used to remove lead, mercury, or other heavy metals from the body. Discuss the advantages and disadvantages of such treatment. Include both thermodynamic and kinetic arguments in your answer. 

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