Search results for "Ferric"
showing 10 items of 166 documents
Reduced graphene oxide-based magnetic composite for trace determination of polycyclic aromatic hydrocarbons in cosmetics by stir bar sorptive dispers…
2020
This work describes a sensitive and rapid analytical method for trace determination of polycyclic aromatic hydrocarbons (PAHs) in cosmetic samples. The proposed method is based on stir bar sorptive-dispersive microextraction (SBSDME). A magnetic composite made of CoFe2O4 magnetic nanoparticles embedded into reduced graphene oxide sheets is used as sorbent phase. After the extraction, the target analytes are desorbed in toluene and then analyzed by gas chromatography-mass spectrometry (GC-MS). The main parameters involved in the extraction procedure (i.e., composite amount, extraction time and desorption time) were evaluated and optimized to provide the best extraction efficiency. The method…
Preconcentration of emerging contaminants in environmental water samples by using silica supported Fe3O4 magnetic nanoparticles for improving mass de…
2011
A magnetic material based on Fe(3)O(4) magnetic nanoparticles incorporated in a silica matrix by using a sol-gel procedure has been used to extract and preconcentrate emerging contaminants such as acetylsalicylic acid, acetaminophen, diclofenac and ibuprofen from environmental water samples prior to the analysis with Capillary LC-MS. The use of the proposed silica supported Fe(3)O(4) magnetic nanoparticles enables surfactant free extracts for the analysis with MS detection without interferences in the ionisation step. Under the optimum conditions, we demonstrated the reusability of the magnetic sorbent material during 20 uses without loss in the extraction efficiency. In addition, no cleanu…
Localization and Characterization of Ferritin in Demospongiae: A Possible Role on Spiculogenesis
2014
Iron, as inorganic ion or as oxide, is widely used by biological systems in a myriad of biological functions (e.g., enzymatic, gene activation and/or regulation). In particular, marine organisms containing silica structures—diatoms and sponges—grow preferentially in the presence of iron. Using primary sponge cell culture from S. domuncula–primmorphs—as an in vitro model to study the Demospongiae spiculogenesis, we found the presence of agglomerates 50 nm in diameter exclusively inside sponge specialized cells called sclerocytes. A clear phase/material separation is observed between the agglomerates and the initial stages of intracellular spicule formation. STEM-HRTEM-EDX analysis of the agg…
Oxidative nuclease activity of ferromagnetically coupled μ-hydroxo-μ-propionato copper(II) complexes [Cu3(L)2(μ-OH)2(μ-propionato)2] (L=N-(pyrid-2-yl…
2008
Three doubly-bridged, trinuclear copper(II) compounds with hydroxo and carboxylato bridges, ∞ 1 [Cu 3 (L1) 2 (μ-OH) 2 (μ-propionato) 2 ] ∞ 1 [ Cu 3 ( L 1 ) 2 ( μ - OH ) 2 ( μ - propionato ) 2 ] (1) , [Cu 3 (L2) 2 (μ-OH) 2 (μ-propionato) 2 (DMF) 2 ] (2) and ∞ 1 {[Cu 3 (L3) 2 (μ-OH) 2 (μ-propionato) 2 ]} ∞ 1 { [ Cu 3 ( L 3 ) 2 ( μ - OH ) 2 ( μ - propionato ) 2 ] } [Cu 3 (L3) 2 (μ-OH) 2 (μ-propionato) 2 (DMF) 2 ]} (3) [HL1 = N -(pyrid-2-ylmethyl)benzenesulfonylamide, HL2 = N -(pyrid-2-ylmethyl)toluenesulfonylamide, HL3 = N -(pyrid-2-ylmethyl)naphthalenesulfonylamide], have been synthesized and characterized. 1 is built from [Cu 3 (L1) 2 (μ-OH) 2 (μ-propionato) 2 ] clusters. Each unit contai…
Synthesis of new half sandwich tetrachloro derivatives of molybdenum(V) and tungsten(V). X-ray structures of (C5HPri4)W(CO)3(CH3) and (C5Et5)WCl4
2002
International audience; The new synthetic intermediates (Ring)MCl4 [Ring=C5HPri4 or 4Cp, M=Mo, 2; Ring=C5Et5 or VCp, M=W, 4, Ring=4Cp, M=W, 6] containing sterically protecting cyclopentadienyl ligands have been synthesized. Along the synthetic pathway to 2, it was found that the treatment of [4CpMo(CO)3]− with an aqueous ferric solution according to the well established Manning procedure affords the hydride compound 4CpMo(CO)3H (1) by hydrolysis rather than the expected neutral dimer by oxidation. Compound 1 could be converted, however, to 2 upon oxidation with PhICl2 in good yields. Compound 4 is shown by a single crystal X-ray analysis to adopt a monomeric four-legged piano stool structur…
Iron(III) bis(pyrazol-1-yl)acetate based decanuclear metallacycles: synthesis, structure, magnetic properties and DFT calculations
2016
The synthesis, structural aspects, magnetic interpretation and theoretical rationalizations for a new member of the ferric wheel family, a decanuclear iron(III) complex with the formula [Fe10(bdtbpza)10(μ2-OCH3)20] (1), featuring the N,N,O tridentate bis(3,5-di-tert-butylpyrazol-1-yl)acetate ligand, are reported. The influence of the steric effect on both the core geometry and coordination mode is observed. Temperature dependent (2.0–300 K range) magnetic susceptibility studies carried out on complexes 1 established unequivocally antiferromagnetic (AF) interactions between high-spin iron(III) centers (S = 5/2), leading to a ground state S = 0. The mechanism of AF intramolecular coupling was…
Superparamagnetic γ-Fe2O3 nanoparticles with tailored functionality for protein separation
2007
Polymer coated superparamagnetic gamma-Fe(2)O(3) nanoparticles were derivatized with a synthetic double-stranded RNA [poly(IC)], a known allosteric activator of the latent (2-5)A synthetase, to separate a single 35 kDa protein from a crude extract which cross reacted with antibodies raised against the sponge enzyme.
Potential Application of Voltammetry of Microparticles for Dating Porcine Blood-based Binding Media used in Taiwanese Architectural Polychromies
2012
A method for dating Hemoglobine-containing archaeological samples using the voltammetry of microparticles is described. This is based on the record of the voltammetric response of such materials attached to paraffin-impregnated graphite electrodes in contact with aqueous acetate buffer. Signals attributable to the Fe(III)/Fe(II) iron couple and their catalytic enhancement in the presence of H(2)O(2) can be correlated, via first-order reaction kinetics, with the time of aging of the samples. The method has been applied to the study and dating of the polychromed architectural decoration of different parts of the architectural complex of the Longshan Temple in Lukang (18(th) century, Taiwan).
Hindering the formation of ferrocenes: mono(cyclopentadienyl)halo iron complexes [Fe(C5R5)X] containing a sterically bulky cyclopentadienyl ligand
2001
Abstract The reaction of lithium 1,2,4-tris(trimethylsilyl)cyclopentadienide Li(Si 3 Cp) with ferrous halide FeX 2 (X=Cl, Br, I) in THF at −95 °C gives a thermally extremely sensitive compound that can be regarded as a functional equivalent for the 14-electron fragment [Fe(Si 3 Cp)X]. Experiments to trap this species with TMEDA gives thermally sensitive, colorless, paramagnetic crystals of the composition [LiFe(Si 3 Cp)Cl 2 (TMEDA) 3 ]. Trimethylphosphite gives isolable 18-electron half-sandwich complexes [Fe(Si 3 Cp){P(OMe) 3 } 2 X]. [Fe(Si 3 Cp)X] is also formed by reducing the ferric derivative [Fe(Si 3 Cp)Cl 2 ] with zinc. Analogous reactivity towards ferrous halides is observed for the…
Comparative toxicity and cell-tissue distribution study on nanoparticular iron complexes using avian embryos and HepG2-cells
2007
In this study the toxicity and intracellular availability of iron from iron dextran (FeD), iron sucrose (FeS), and iron gluconate (FeG) was compared in organs of avian (turkey) embryos and in isolated cells (HepG2) in cell culture. Iron uptake was more pronounced in embryonic liver than in renal tissue. Cellular iron uptake in liver and kidney was more or less similar for the different compounds. Only some experiments showed slightly greater iron concentrations in liver and kidney with FeG compared with FeD and FeS. Significant differences were found in the survival ratios of the eggs and the embryo weights depending on the type of iron complex administered. The rank order of toxicities was…