Divalent Nickel Ions Research Articles

Separation and recovery of cobalt(II) and nickel(II) from sulphate solutions using sodium salts of D2EHPA, PC 88A and Cyanex 272

Separation and recovery of divalent cobalt and nickel ions from sulphate solutions containing 0.01 M metal ions each and 0.1 M Na 2SO 4 have been carried out using 0.03, 0.05 and 0.06 M sodium salts of D2EHPA, PC 88A and Cyanex 272 in kerosene. The percentage extraction of metal ions increased with increasing equilibrium pH. Cobalt was preferentially extracted over nickel with the extractants; however, 0.05 M NaPC 88A and NaCyanex 272 were found to be suitable for the separation study. The highest separation factor was achieved with 0.05 M NaCyanex 272 at equilibrium pH 6.85. Recovery of cobalt from cobalt–nickel bearing solution was achieved with 0.05 M Cyanex 272 and PC 88A at equal phase ratio followed by their stripping with 0.02 M H 2SO 4 at O:A ratio of 2:1. Nickel was extracted from the cobalt-free raffinate in two stages at equal phase ratio with PC 88A and Cyanex 272 followed by their stripping with 0.02 M H 2SO 4 at O:A ratio of 4:3 and 2:1, respectively.

Thermally stimulated depolarization currents in nickel doped NaCI crystals

Depolarization currents have been investigated for thermally and mechanically pretreated NaCI crystals doped with divalent nickel ions. The models of Debye and Maxwell-Wagner-Sillars polarizations have been exploited to describe the behavior of ITC bands detected below (dipolar), near and above (interfacial) room temperature, respectively. The NaCI:Ni2+ system was especially interesting for kinetic studies because the dopant ions are distinctly smaller than the matrix cations. It has been found that the precipitation phenomena can be understood in terms of an Avramiapproach of the process mainly occurring in the stress fields of dislocations. The migration of impurities is controlled by the diffusion of cation vacancies.

METAL (HARDWARE) IMPLANT “ALLERGY”

An essential attribute of all implanted surgical material must be an inherent inertness. Whereas to surgical implants are at times suspected, definitive association of a reaction caused by implant material is only rarely documented. Because there is no single source describing the incidence, clinical manifestations, pathogenesis, diagnosis, and management of such reactions, this article reviews the literature and attempts to interpret such reactions in light of the present knowledge of allergic and irritant contact metal of the skin and bone. Although the true incidence of contact from orthopedic implants may be rare, contact to metals is one of the most common causes of allergic contact dermatitis (ACD), as reported by both the North American Contact Dermatitis Group (NACDG) and the International Contact Dermatitis Research Group (ICDRG). 45 Nickel, cobalt, and chromium are the most constant offenders of all the allergenic metals. Nickel is the most frequent of all reported metal allergies 10 ; 10% of females are reported to be allergic to nickel. Dotterud and Falk 10 noted an increasing prevalence of nickel sensitivity in 201 school girls, which they ascribed to the higher incidence of ear piercing. They found the prevalence of nickel in girls with pierced ears to be twice as high as in girls without pierced ears (30.8% versus 16.3%, respectively). Nickel sensitivity in 223 boys was much lower, with but a few boys having pierced ears (11/223, or 5%). Nickel has also been reported to be one of the most frequent causes of occupational dermatoses. Of 853 hard-metal workers (485 males and 368 females), approximately 5% (2 males and 38 females) were positive to nickel on patch testing. Eighty-eight percent of the positives reported a history of costume jewelry allergy prior to their employment in the hard-metal industry. Forty percent of those allergic to nickel developed a recalcitrant hand eczema during the first year of employment, and 36 of 38 nickel-sensitive women had pierced ears. 43 Not only does nickel produce an eczematous (delayed-type hypersensitivity) reaction, but it has also been reported to cause immediate-type (IgE/mast-cell-induced) allergic reactions. The divalent nickel ion can be antigenic via contact, by ingestion, or by inhalation. The latter antigenic presentations may also cause clinical reactions, such as urticaria, with or without wheezing. Cobalt compounds can produce a wide range of immunologic reactions, plus pose an irritant-type problem of skin toxicity, especially in the workplace. Cobalt has been noted to occur concomitantly with nickel allergy. Rystedt and Fisher 43 report an incidence of 25% of nickel-sensitive individuals were also allergic to cobalt. Chromium is one of the less toxic heavy metals, but its salts can induce an irritant contact dermatitis (ICD). Trivalent chromium is the least reactive because of its relative inability to penetrate the skin. Hexavalent chromium, however, is the compound mostly associated with ICD. Many hexavalent chromium compounds are corrosive irritants, sensitizers, and respiratory carcinogens. 19 Sensitization to chromium enhances cobalt sensitization, which frequently occurs in nickel-sensitive individuals. These are not considered to be cross-reactions, but more likely distinctive, unique sensitizations to each individual metal. 24 The prevalence of these metals in the environment is high.

Formation of Phenolate Complexes of Some First-Row Transition Metal Cations

We report in the present paper the result of our potentiometric studies on the complexation tendency of phenolate anion with divalent manganese, cobalt, nickel, and copper ions in aqueous sodium pperchlorate solutions of 0.1 M ionic strenght at 25.0°

Derivative spectrophotometry in the determination of metal ions with 4-(pyridyl-2-azo)resorcinol (PAR).

Derivative spectrophotometry has been applied for the elimination of the mutual spectral interferences and the analysis of binary, ternary and quaternary mixtures of complexes of microgram amounts of divalent ions of cobalt, copper, lead, manganese, nickel, zinc and iron with 4-(pyridyl-2-azo)resorcinol (PAR) in the range of 0.05-1 microg/ml (0.2-4 microg/ml for lead). The first derivative spectra can be used for the determination of both components in the majority of binary mixtures except of Cu(II) and Co(II) and systems containing Fe(II). The second and the third derivative spectra allow to determine one constituent in some ternary and quaternary mixtures.

Potentiometric and thermal conductimetric studies on salicylidene Girard-P hydrazone complexes of divalent Co, Ni, Cu and Zn salts

Salicylidene Girard-P hydrazone [H2L]Cl reacts with divalent cobalt, nickel, copper and zinc ions to form mono-ligand complexes of the type [ML·H2O]Cl·nH2O and [(CuL)2]Cl2. The formation constants of the complexesML were determined in 50% (v/v) aqueous ethanol solution at an ionic strengthl=0.1M KCl and at 25±0.1°C. The solid complexes and the ligand were subjected to differential thermal analysis and the DC electrical conductivities were measured at varying temperatures. The results obtained were explained and discussed in terms of the proposed semiconductive behaviour of the complexes and the probable occurrence of a phase transition. The activation energies (ΔE) were calculated for the ligand and the complexes; that of the ligand was higher than those of the complexes.

HypB protein of Bradyrhizobium japonicum is a metal-binding GTPase capable of binding 18 divalent nickel ions per dimer.

Bradyrhizobium japonicum hypB encodes a protein containing an extremely histidine-rich region (24 histidine residues within a 39-amino-acid stretch) and guanine nucleotide-binding domains. The product of the hypB gene was overexpressed in Escherichia coli and purified by Ni(2+)-charged metal chelate affinity chromatography (MCAC) in a single step. In SDS/PAGE, HypB migrated at 38 kDa--slightly larger than the calculated molecular mass (32.8 kDa). Purified HypB has GTPase activity with a kcat of 0.18 min-1 and a Km for GTP of 7 microM, and it has dGTPase activity as well. HypB exists as a dimer of molecular mass 78 kDa in native solution as determined by fast protein liquid chromatography on Superose 12. It binds 9.0 +/- 0.14 divalent nickel ions per monomer (18 Ni2+ per dimer) with a Kd of 2.3 microM; it also binds Zn2+, Cu2+, Co2+, Cd2+, and Mn2+. In-frame deletion of the histidine-rich region (deletion of 38 amino acids including 23 histidine residues) resulted in a truncated HypB that did not bind to the MCAC column, whereas in-frame deletion of 14 amino acids including 8 histidine residues within HypB resulted in a truncated HypB that still bound to the column. The results indicate that the histidine residues within the histidine-rich region of HypB are involved in metal binding.

A single stranded DNA binding protein isolated from HeLa cells facilitates Ni2+ activation of DNA polymerases in vitro.

The divalent nickel ion (Ni2+) is one of several metal ions that can substitute for Mg2+ in the activation of DNA polymerases in vitro, but usually with very low efficiency. We have purified and partially characterized a Ni(2+)-binding protein (p40) from HeLa cell extracts that can specifically enhance the polymerase activity of DNA polymerase alpha (pol alpha) and other DNA polymerases in response to Ni2+. This protein, with a molecular mass of 40 kDa, is a single stranded DNA binding protein that binds to a M13 DNA template-primer with an optimum stoichiometry of approximately 90 equiv of protein per equiv of DNA template and enhances the affinity of pol alpha for the primer-template. In the presence of Ni2+, p40 exhibits an increased affinity for DNA. The p40 increased by 3- to 6-fold the rates at which pol alpha and the Klenow fragment of Escherichia coli DNA polymerase I (KF) replicate different DNA templates in response to Ni2+. The low processivity of Ni(2+)-activated pol on primed M13 ssDNA was also enhanced by the presence of p40. The rates of Ni(2+)-dependent replication by inherently more processive enzymes, DNA polymerase delta and T4 DNA polymerase, were not significantly increased by p40 when M13 ssDNA was used as a template; however, p40 did increase the activity of T4 polymerase on an activated calf thymus DNA template. The protein did not stimulate Mg(2+)-activated DNA replication.

Simultaneous spectrophotometric determination of metal ions with 4-(pyridyl-2-azo)resorcinol (PAR)

A new method for the simultaneous determination of the divalent ions of cadmium, cobalt, copper, lead, manganese, nickel and zinc in binary, ternary and quaternary mixtures based on the application of a multiple linear regression programme to the spectra of the complexes of these ions with 4-(pyridyl-2-azo)resorcinol (PAR) was developed. The detection limits afforded by the proposed method range from 0.02 μg/ml for Co(II), Mn(II), Ni(II) and Zn(II) to 0.10 μg/ml for Pb(II). The method is rapid and quite simple as it entails no prior separation, and was successfully applied to the analysis for the above-mentioned ions in synthetic samples and real alloys.

Synthesis and characterization of square planar and pseudo-tetrahedral M(II)N 2S 2

Copper(II), nickel(II) and zinc(II) complexes of methyl-2-amino-1-cyclopentenedithiocarboxylate and N,N′-pentamethylene-bis(methyl-2-amino-1-cyclopentenedithiocarboxylate) have been prepared and characterized in order to provide a basis for comparison of neutral molecules involved in planar and pseudo-tetrahedral coordination geometries with similar N 2S 2 ligand donor sets. Methyl-2-amino-1- cyclopentenedithiocarboxylate chelates as a bidentate ligand through a thioketonate sulfur and an imine nitrogen, forming planar complexes with the divalent ions of copper(II), nickel(II) and zinc(II). The Cu(II) complex exhibits EPR spin Hamiltonian parameters typical of an axial system with g∥=2.139 and A∥=175x10 −4. N,N′-pentamethylene-bis(methyl-2-amino-1-cyclopentenedithiocarboxylate) coordinates as a tetradentate ligand, where the pentamethylene bridge between the nitrogens introduces steric strain forcing distortion of the inner coordination sphere. Spectral data support pseudo-tetrahedral coordination geometries for both Cu(II) and Ni(II). The EPR spectrum of this Cu(II) complex is characteristic of a large tetrahedral distortion with g∥=2.146 and A∥=133x10 −4cm −1, while 1H NMR studies on the Ni(II) analogue indicate paramagnetic contact shifts of resonances, also indicative of tetrahedral distortion. The complexes are examined as possible spectral models of N 2S 2 coordination environments at the active sites of metalloproteins such as in the type I blue copper(II) and nickel hydrogenase proteins.

Paramagnetic properties of the divalent nickel ions in some alkali borate glasses

Paramagnetic properties of the divalent nickel ions in some alkali borate glasses

Nickel adsorption on a platinized platinum electrode

The electrodeposition of nickel on a platinum electrode from a divalent nickel ion solution under UPD conditions has been studied by radiometric and voltammetric methods. The dependencies of surface concentration of adsorbed nickel on the electrode potential, nickel ion concentrations in acid and neutral solutions have been determined. From the radiometric and voltammetric data the electrosorption valency, /gg, has been calculated. The change of /gg with θ has been discussed.

Transition-metal complexes of dithiooxamide ligands. Vibrational fine structure in the electronic spectra of symmetrically N,N'-disubstituted dithiooxamides and their divalent nickel ion complexes

Transition-metal complexes of dithiooxamide ligands. Vibrational fine structure in the electronic spectra of symmetrically N,N'-disubstituted dithiooxamides and their divalent nickel ion complexes

Activation of hypoxanthine/guanine phosphoribosyltransferase from yeast by divalent zinc and nickel ions

We have observed previously that the reactions catalyzed by hypoxanthine/guanine phosphoribosyltransferase (HGPRTase) are activated by Mg(II), Mn(II), and Co(II), and we have defined the mechanism by which these activations proceed [ Biochemistry 22, 3419–3424 (1983)]. A more extensive survey of the kinds of metal ions that will activate the HGPRTase catalysis now has been completed through the use of an HPLC assay procedure. Although Fe(II) and Ca(II) are unable to activate this reaction, a significant activation was achieved with the addition of spectroscopically pure Zn(II) to the assay solution. In addition some IMP synthesis resulted from the addition of Ni(II) to the assay mixture. Both the Zn(II) and Ni(II) kinetic effects on HGPRTase over a limited metal ion concentration range have been analyzed through the use of curve-fitting exercises. These results, in addition to the similar pH profiles for the activations by Mg(II), Mn(II), Co(II), and Zn(II), suggest that all of these metal ions activate the HGPRTase-catalyzed synthesis of IMP by way of the same mechanism [model II as defined by London and Steck, Biochemistry 8, 1767–1779 (1969)], during which two divalent ions bind to the HGPRTase active site per molecule of PRibPP.

ChemInform Abstract: Complexation of Divalent and Trivalent Nickel and Copper Ions by Rigid and Flexible Dioxo Tetraaza Macrocycles.

AbstractPotentiometric, spectrophotometric, kinetic, and electrochemical studies on the Ni(II) and Cu(II) complexes with the macrocycles (I) and (II) are performed to investigate the importance of the flexibility of the macrocyclic ring to the properties of the corresponding complexes.

Complexation of divalent and trivalent nickel and copper ions by rigid and flexible dioxo tetraaza macrocycles

Etude de l'influence de la flexibilite du macrocycle sur les proprietes des complexes correspondants

Effect of gamma-rays on some mixed alkali borate glasses containing nickel

The change of optical absorption of some irradiated mixed alkali borate glasses containing nickel has been studied by varying the gamma-ray dose or the mixed alkali oxide content. The induced bands increase as the radiation process proceeds until a certain limit after which a constancy is assumed to be reached. The investigation of the observed spectra shows that there is an induced absorption band with its maximum at 550 nm, in addition to the characteristic absorption bands of the divalent nickel ions with peaks in the visible region at 410, 640, 680 and 750 nm.

EOR fine structure of divalent nickel ions in powders and single crystals of hexakis-imidazole-nickel(II) nitrate

The EPR spectral parameters of Ni 2+ in the complex compound [Ni(C 3H 4N 2) 6](NO 3) 2 of trigonal symmetry are determined from measurements on the powder and monocrystal. The EPR profile shape of powder samples measured at 9.3 and 36 GHz is compared with that plotted on the basis of numerical simulation. The EPR parameters from the simulation procedure correspond to axial symmetry of the spin Hamiltonian, and differ but insignificantly from those determined on the basis of the anisotropy of the single-crystal spectrum: g = 2.185, D = 0.882 cm −1, E = 0.

The role of metals in carcinogenesis: biochemistry and metabolism.

The oxyanions of vanadium, chromium, molybdenum, arsenic, and selenium are stable forms of these elements in high oxidation states which cross cell membranes using the normal phosphate and/or sulfate transport systems of the cell. Once inside the cell, these oxyanions may sulfuryl transfer reactions. Often the oxyanions serve as alternate enzyme substrates but form ester products which are hydrolytically unstable compared with the sulfate and phosphate esters and, therefore, decompose readily in aqueous solution. Arsenite and selenite are capable of reacting with sulfhydryl groups in proteins. Some cells are able to metabolize redox active oxyanions to forms of the elements in other stable oxidation states. Specific enzymes may be involved in the metabolic processes. The metabolites of these elements may form complexes with small molecules, proteins and nucleic acids which inhibit their ability to function properly. The divalent ions of beryllium, manganese, cobalt, nickel, cadmium, mercury, and lead are stable forms of these elements which may mimic essential divalent ions such as magnesium, calcium, iron, copper, or zinc. These ions may complex small molecules, enzymes, and nucleic acids in such a way that the normal activity of these species is altered. Free radicals may be produced in the presence of these metal ions which damage critical cellular molecules.

The Role of Metals in Carcinogenesis: Biochemistry and Metabolism

The oxyanions of vanadium, chromium, molybdenum, arsenic, and selenium are stable forms of these elements in high oxidation states which cross cell membranes using the normal phosphate and/or sulfate transport systems of the cell. Once inside the cell, these oxyanions may sulfuryl transfer reactions. Often the oxyanions serve as alternate enzyme substrates but form ester products which are hydrolytically unstable compared with the sulfate and phosphate esters and, therefore, decompose readily in aqueous solution. Arsenite and selenite are capable of reacting with sulfhydryl groups in proteins. Some cells are able to metabolize redox active oxyanions to forms of the elements in other stable oxidation states. Specific enzymes may be involved in the metabolic processes. The metabolites of these elements may form complexes with small molecules, proteins and nucleic acids which inhibit their ability to function properly. The divalent ions of beryllium, manganese, cobalt, nickel, cadmium, mercury, and lead are stable forms of these elements which may mimic essential divalent ions such as magnesium, calcium, iron, copper, or zinc. These ions may complex small molecules, enzymes, and nucleic acids in such a way that the normal activity of these species is altered. Free radicals may be produced in the presence of these metal ions which damage critical cellular molecules.