A sensitive and simultaneous spectrophotometric flow injection method for the determination of vanadium(IV) and vanadium(V) is proposed. The method is based on the effect of ligands such as 2,4,6-tris(2-pyridyl)-1,3,5-triazine (TPTZ) and diphosphate on the conditional redox potential of iron(III)/iron(II) system. A four-channel flow system is assembled. In this flow system, diluted hydrochloric...

Only 9 (11.2%) out of 80 studied bacterial strains were able to utilize iron saturated 2-oxo acids and hydroxyacids and grow on o-phenantroline containing media. These strains belonged to Enterococcus faecalis and Enterococcus faecium species and were isolated from clinical material. Iron sources utilized by all of these strains were Fe(III) complexes with pyruvic, 2-oxobutyric, 4-methylthio-2-...

The equilibrium constants and kinetics for the complexing of aqueous iron(m) by 2,3dihydroxybenzoic acid (DHB) and 1,2-dihydroxy-3~-benzenedisulfo~te (Tiron) have been studied with iron(IIl) in excess over ligand. Formation constant comparisons indicate that DHB complexes in a mode analogous to salicylate. The reaction rate has the hydrogen ion dependence typical for iron(m) complexation, but t...

Previous work from our laboratory demonstrated that pyridoxal isonicotinoyl hydrazone (PIH) has in vitro antioxidant activity against iron plus ascorbate-induced 2-deoxyribose degradation due to its ability to chelate iron; the resulting Fe(III)-PIH(2) complex is supposedly unable to catalyze oxyradical formation. A putative step in the antioxidant action of PIH is the inhibition of Fe(III)-med...

the interaction of hgh with some metal ions ( ) at 27°c in nac1 solution, 50 mm was studied using isothermal titration calorimetry. there is a set of three identical and non-interacting binding sites for binding of all these metal ions, expect . the intrinsic association equilibrium constants () are not very different for  and , and also their molar enthalpies of binding (kj/mol for  and  kj/mo...

Iron is an essential nutrient for many microbes. According to the "Trojan Horse Hypothesis", biological systems have difficulties distinguishing between Fe(3+) and Ga(3+), which constitutes the antimicrobial efficacy of the gallium(iii) ion. Nine novel tris(quinolono)gallium(iii) complexes and their corresponding iron(iii) analogs have been synthesized and fully characterized. Quinolone antimic...

We have designed two subfamilies of lipophilic iron (III) chelators previously termed reversed siderophores (RSFs). The agents display physicochemical properties that favor extraction of iron beyond membrane barriers of Plasmodium falciparum-infected red blood cells. We studied the in vitro antimalarial potency of RSFs and their relationship to the membrane permeation properties of these agents...

Iron (III) oxide (Fe2O3) is an excellent material for absorbing visible light from the solar spectrum because of its suitable band gap. However, due to low mobility and high bulk carrier recombination, the photoconversion efficiency of iron (III) oxide has been proven to be very poor. Fabrication of nanostructured iron oxide can potentially compensate for the material’s poor properties. In this...

The presented review is devoted to analytical applications of reactions of Fe(III) and K(3)[Fe(CN)(6)] with 2,10-disubstituted phenothiazines (PT). It was found that iron(III) and hexacyanoferrate(III) ions in acidic media easily oxidized PT with the formation of colored oxidation products. This property has been exploited for spectrophotometric determination of iron(III) ions and phenothiazine...