Use as chelating agents

Bunte salts have bacterial, insecticidal, and fungicidal properties, and are also used as chelating agents (qv) or surfactants (qv) (97,98). Bunte salts have been tested for preirradiation protection for mammals exposed to lethal radiation doses (99,100) (see Radioprotectiveagents). 

Either particulate sol or polymeric sol has been used for thin film coatings. The polymeric sol was fabricated by partial hydrolysis of corresponding metal alkoxide. If the rate of hydrolysis or condensation is very fast, then some kinds of organic acids, beta-dicarbonyls, and alkanolamines have been used as chelating agent in sol-gel processes to control the extent and direction of the hydrolysis-condensation reaction by forming a strong complex with alkoxide. [2]. 

Calcium or zinc complexes of polycarboxylate compounds such as DTPA or ethylenediaminetetratacetic acid (EDTA) have been used as chelating agents to accelerate the urinary excretion of americium in humans who were accidentally exposed to americium (Breitenstein 1983 Doerfel and Oliveira 1989 ... 

Applications for the 1,10-phenanthroline nucleus are widespread for example, they have been used as chelating agents (see Section 10.23.5.2), ligands for catalysis (see Section 10.23.5.2), as cytotoxic drugs <2002T9095>, and, when complexed with molybdenum, as cancer therapeutics <2005W0087783>. 

By use of different detectors trace amounts of metals ranging from 10 to 10 g can be determined (Tables l.l/II, 1.2). Polyfluorinated 3-diketones as ligands give more highly volatile derivatives and above all allow the use of the electron capture detector (ECD) which has low detection limits for fluorinated compounds. Nevertheless decompositions can also appear in this class of substances. In addition thioketones and amino derivatives are used as chelating agents for quantitative gas-chromatography. 

Other extraction agents such as dithizone, diethyl dithiocarbamates, and 8-hydroxy-quinoline (oxine) are also useful as chelating agents and extract several metals including transition metals, alkali and alkaline metals. The dithizone can extract up to 20 elements and these complexes behave the same and there is no additional advantage of using one over the other. The compound 8-hydroxyquinoline will form stable complexes with Al, Ca, Sr and Mg at pH 8.0 these metals form unstable complexes with APDC. At carefully controlled pH the oxidation states of metals may also separated, e.g. Fe[II] and Fe[III], The stmcture of 8-hydroxyquinoline is ... 

Grafting of 2-methyl-2-oxazoline from chloromethylated polystyrene beads in benzonitrile at 110 °C gave graft copolymers, which were hydrolysed to poly(styrene-g-ethyleneimine) and used as chelating agents. 

USE As chelating agent [or trivalent iron from pH 7 to pH 10. Forms strong 1 l ferric chelates. The iron chelates formed will then chelate other heavy metal or alkaline earth ions. 

Useful as chelating agents in treating diseases associated with excess Fe (HI). 

A poly(imide-siloxane)/titania hybrid film was fabricated by a sol-gel process by the in situ formation of titania within the poly(imide-siloxane) matrix [85]. The poly(amic acid siloxane) polymer was prepared from 4,4 -oxydiphthalic anhydride, 2, 2-bis [4-(4-aminophenoxy) phenyl] propane, and a,a>-bis(3-aminopropyl)polydimethylsiloxane. Acetylace-tone was used as chelating agent in order to reduce the rate of hydrolysis of titanium alkoxide in the polymer. The presence of titania on the surface of eventually produced films enhances the adhesive strength at the interface. 

Derivatives of quinolines have been used as chelating agents for copper extraction. The most well known is 7-alkeny1-8-hydroquinoline and has the trade name KELEX 100 (see Fiure 2) (52). Substituted 8-sul-... 

Ethylenediamine tetraacetic acid (EDTA) is preferably used as chelating agent. EDTA effects a greatly reduced yellowness index. 

Uses as chelating agent for metals and as pharmaceutic aid (chelating agent) as preservative in cosmetic products anticoagulant. A... 

It is used as chelating agent for heavy metals, in clarification of red wine and as an anticorrosion agent. 

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