Preparation of hydrazinodeoxycellulose and carboxyalkyl hydrazinodeoxycelluloses and their adsorption behavior toward heavy metal ions

Nitrogen-containing cellulose derivatives hydrazinodeoxycellulose (HDC) and carboxyalkyl hydrazinodeoxycelluloses (α- and β-CAHDCs) were prepared from 6-chlorodeoxycellulose (CDC). Their adsorption of divalent transition metal ions was determined from dilute aqueous solutions and compared with that of aminoalkyl celluloses (AmACs) reported previously. HDC scarcely adsorbs metal ions in the pH range of 1–2, whereas α- and β-CAHDCs adsorb metal ions in this pH range. However, the adsorption of metal ions on HDC increases rapidly with increasing pH and HDC more effectively adsorbs metal ions than α- and β-CAHDCs in weakly acidic conditions. The ability to adsorb Cu²⁺ ions was in the order of AmAC (carbon number in the diamine moiety m = 2) > HDC > α-CAHDC > β-CAHDC in the weakly acidic region. These adsorbents selectively adsorb Cu²⁺ ions from the solutions containing other metal ions such as Mn²⁺, Co²⁺, and Ni²⁺, and the Irving–Williams series is obeyed in these adsorbent/metal ion systems. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 3359–3363, 1997     

Purification of monoclonal antibodies, IgG1, from cell culture supernatant by use of metal chelate convective interaction media monolithic columns

Monoclonal antibodies (MAbs) have diverse applications in diagnostics and therapeutics. The recent advancement in hybridoma technology for large‐scale production of MAbs in bioreactors demands rapid and efficient purification methods. Conventional affinity purification systems have drawbacks of low flow rates and denaturation of antibodies owing to harsh elution conditions. Here, we attempted purification of MAbs by use of a high‐throughput metal–chelate methacrylate monolithic system. Monolithic macroporous convective interaction media–iminodiacetate (CIM‐IDA) disks immobilized with four different metal ions (Cu²⁺, Ni²⁺, Zn²⁺ and Co²⁺) were used and evaluated for purification of anti‐human serum albumin IgG1 mouse MAbs from cell culture supernatant after precipitation with 50% ammonium sulfate. Elution with 10 mM imidazole in the equilibration buffer (25 mM MMA = MOPS (Morpholino propane sulfonic acid) + MES (Morpholino ethane sulfonic acid) + Acetate + 0.5 M NaCl, pH 7.4) resulted in a purification of 25.7 ± 2.9‐fold and 32.5 ± 2.6‐fold in experiments done using Zn²⁺ and Co²⁺ metal ions, respectively. The highest recovery of 85.4 ± 1.0% was obtained with a CIM‐IDA‐Zn(II) column. SDS–PAGE, ELISA and immuno‐blot showed that the antibodies recovered were pure, with high antigen‐binding efficiency. Thus, metal chelate CIM monoliths could be a potential alternative to conventional systems for fast and efficient purification of MAbs from the complex cell culture supernatant. Copyright © 2012 John Wiley & Sons, Ltd.     

Construction of template ligand sites in polymeric matrices with dithizone

Metal ion specific template ligand sites were developed by physically immobilizing dithizone molecules oriented according to a particular complex geometry in various polymeric films. Four polymeric systems, polystyrene, poly(methyl methacrylate), poly(vinyl chloride), and polycarbonate, were used for making template sites for Cu²⁺, Ni²⁺, Zn²⁺, and Co²⁺ ions. A high degree of specificity could be achieved independent of stability constants, though about half of the ligand sites were unavailable to the metal ions. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3729–3734, 1997     

New Electrocatalytic Reactions at a Mercury Electrode in the Presence of Homocysteine or Cysteine and Cobalt or Nickel Ions

Homocysteine (Hcy) and cysteine (Cys) mercury thiolate layers were prepared by anodic polarization of a mercury electrode in amino acid containing solutions and then investigated in the cathodic regime in the presence of Ni²⁺ or Co²⁺ ions. The sulfhydryl function in the mercury thiolate undergoes a slow disintegration resulting in surface‐attached mercury sulfide. During the cathodic scan, Hg²⁺ substitution by Ni²⁺ or Co²⁺ yields minute amounts of the relevant metal sulfide. Such a species catalyzes hydrogen evolution at ?1.3 V vs. Ag|AgCl|KCl(3 M). Hcy experiences a faster decomposition and, consequently, displays a stronger catalytic effect. Each compound catalyzes the reduction of Ni²⁺ or Co²⁺, but only Cys (bound in metal complexes) induces typical catalytic hydrogen evolution processes such as the Brdi?ka reaction (with Co²⁺; pH around 9), or the catalytic hydrogen prewave (CHP) (with Ni²⁺; pH near 7). On the other hand, Hcy catalyzes the hydrogen evolution in the presence of Co²⁺ at ?1.5 V in the same way than sulfur derivatives with no amine function do. Metal sulfide formation does not interfere with CHP and Brdi?ka processes. Correlations between the physical state of the metal sulfide (adsorbed molecule or aggregate form) and its catalytic properties are discussed and possible analytical applications suggested.     

Novel polyamidoamine‐based hydrogel with an innovative molecular architecture as a Co2+‐, Ni2+‐, and Cu2+‐sorbing material: Cyclovoltammetry and extended X‐ray absorption fine structure studies

An amphoteric polyamidoamine (PAA)‐based hydrogel, named INT‐PAA1, with a novel molecular architecture was prepared and studied as a Co²⁺‐, Ni²⁺‐, and Cu²⁺‐sorbing material. This hydrogel was obtained by the synthesis of a PAA in the presence of a second presynthesized PAA carrying many primary amino groups as side substituents, which acted as a macromolecular crosslinking agent. Therefore, it had an intersegmented structure. INT‐PAA1 exhibited a remarkable sorption capacity and sorption rate for Co²⁺, Ni²⁺, and Cu²⁺ that were advantageously in situ monitored by cyclic voltammetry. An extended X‐ray absorption fine structure spectroscopy characterization of the Co²⁺/INT‐PAA1 complex was also performed. The very fast and quantitative metal‐ion uptake, made apparent by an intense coloring of the hydrogel, showed remarkable potential for environmental applications such as heavy‐metal detection, recovery, and elimination. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2316–2327, 2006     

Template effects in chelating polymers

Poly(4′-methyl-4-vinyl-2,2′-bipyridine) has been prepared as have various copolymers with divinylbenzene. When polymerization is carried out in the presence of metal ions (Ni²⁺, Co²⁺, Cu²⁺) a metal-containing copolymer is obtained which, when the metal ion is removed with acid, retains some memory of the original chelating metal.     

Complexation of metal ion with poly(1-vinylimidazole) resin prepared by radiation-induced polymerization with template metal ion

Poly(1-vinylimidazole) (PVI) resin was prepared with Ni²⁺, Co²⁺, or Zn²⁺ as a template to study the adsorption of metal ions. The metal-1-vinylimidazole complex was copolymerized and crosslinked with 1-vinyl-2-pyrrolidone by γ-ray irradiation and the template metal ion was removed by treating the polymer complex with an acid. These PVI resins adsorbed metal ions more effectively than the PVI resin prepared without the template. The number of adsorption sites (As) and the stability constant (K) of Ni²⁺ complex were larger for the PVI resin prepared with the Ni ion template, caused by the smaller dissociation rate constant of Ni ion from the resin. The composition of the Ni²⁺ complex in the resin remained constant. This suggests that the complexation proceeded via a one-step mechanism.     

Thermodynamic studies on complexation of divalent transition metal ions with some zwitterionic buffers for biochemical and physiological research

The interaction between the zwitterionic buffers (3-[N-bis(2-hydroxyethyl)amino]-2-hydroxy propane sulfonic acid, N-(2-actamido)-2-aminoethane sulfonic acid, and 3-[(1,1-dimethyl-2-hydroxyethyl)amino]-2-hydroxy propane sulfonic acid) with some divalent transition metal ions (Cu^II, Ni^II, Co^II, Zn^II, and Mn^II) were studied at different temperatures (298.15 to 328.15) K at ionic strength I = 0.1 mol · dm⁻³ NaNO₃ and in the presence of 10%, 30%, and 50% (w/w) dioxene by using potentiometry. The thermodynamic stability constants were calculated as well as the free energy change for the 1:1 binary complexation. The protonation constants of the zwitterionic buffers were also determined potentiometrically under the above conditions.     

Metal‐Ion‐Mediated Tuning of Duplex DNA Binding by Bis(2‐(2‐pyridyl)‐1H‐benzimidazole)

Studies of double‐stranded‐DNA binding have been performed with three isomeric bis(2‐(n‐pyridyl)‐1H‐benzimidazole)s (n=2, 3, 4). Like the well‐known Hoechst 33258, which is a bisbenzimidazole compound, these three isomers bind to the minor groove of duplex DNA. DNA binding by the three isomers was investigated in the presence of the divalent metal ions Mg²⁺, Co²⁺, Ni²⁺, Cu²⁺, and Zn²⁺. Ligand–DNA interactions were probed with fluorescence and circular dichroism spectroscopy. These studies revealed that the binding of the 2‐pyridyl derivative to DNA is dramatically reduced in the presence of Co²⁺, Ni²⁺, and Cu²⁺ ions and is abolished completely at a ligand/metal‐cation ratio of 1:1. Control experiments done with the isomeric 3‐ and 4‐pyridyl derivatives showed that their binding to DNA is unaffected by the aforementioned transition‐metal ions. The ability of 2‐(2‐pyridyl)benzimidazole to chelate metal ions and the conformational changes of the ligand associated with ion chelation probably led to such unusual binding results for the ortho isomer. The addition of ethylenediaminetetraacetic acid (EDTA) reversed the effects completely.     

Polymeric hydrogels modified with ornithine and lysine: Sorption and release of metal cations and amino acids

A novel, convenient synthesis, using copper ions, is described for the multigram‐scale preparation of acryloyl and methacryloyl ornithine and lysine without the need to use protecting groups and chromatographic purifications. Three methods of removing the copper ions from the amino acid derivatives were examined. The obtained acryloyl and methacryloyl ornithine and lysine were copolymerized with N‐isopropylacrylamide and N,N′‐methylenebisacrylamide as crosslinking agents, resulting in a series of hydrogels with varying incorporated amino acid content. The relative content of a given amino acid was estimated from the ¹H NMR data and compared with its molar fraction used in the polymerization process. We investigated the influence of the amount of amino acid groups incorporated into the polymer network on the swelling behavior of the gels in the presence of metal ions of different ability to form complexes (Cu²⁺, Co²⁺, and Ca²⁺) with α‐amino acid groups and the sorption of copper ions. Next, the presence of α‐amino acid groups attached to the polymer network was used to bond the compounds which can cocomplex metal ions. Phenylalanine was selected for examination of its cocomplexation of Cu²⁺ with the polymer‐network amino acids and its consecutive release from the gel after appropriate change of pH. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

L‐lysine and EDTA polymer mimics as resins for the quantitative and reversible removal of heavy metal ion water pollutants

Traditional precipitation methods for inorganic micropollutant removal from waters are increasingly being replaced by sorption methods based on both natural and synthetic materials. In this context, two novel effective heavy metal ions absorbers are presented. These resins, LYMA and LMT85, were crosslinked poly(amidoamine)s carrying amine and carboxyl groups in their repeating units. In particular, the LYMA‐repeating unit contains one carboxyl and two amine groups and is a mimic of L ‐lysine, whereas LMT85 contains two amine and five carboxyl groups and is a mimic of EDTA. Both resins were prepared at moderate cost by simple eco‐friendly procedures. The heavy metal ion set adopted as benchmark was Cu²⁺, Cd²⁺, Pb²⁺, Zn²⁺, Ni²⁺, and Co²⁺. LYMA proved selective for Cu²⁺ and Ni²⁺, the other ions tested being negligibly absorbed, whereas LMT85 proved capable of rapidly and quantitatively absorbing all the ions tested either singly or in mixed solution. The absorption process was reversible, and the resins were easily regenerated by acidification. The absorption of several metal ions imparted intense coloring to the resins, a feature possibly exploitable for analytical purposes. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Hetero-binuclear chelates of Mn(II), Co(II) and Cu(II) o-cresolphthalein complexonates with other metal ions

Heterobinuclear metal chelates of Mn²⁺, Co²⁺ or Cu²⁺ and some transition metal ions with o-cresolphthalein complexone have been prepared and characterized. Elemental analyses are in agreement with proposed formulae. Thermal analyses (TGA and DTA) were used to determine the degradation products; some thermodynamic parameters were calculated. IR and UV-Vis spectra identified the mode of bonding between the metal ions and the ligand as well as its geometry. Magnetic moment determination and ESR spectra of the heterobinuclear complex revealed some antiferromagnetic interaction between the metal ions, which depends mainly on the two metal ions forming the chelate. Electrochemical studies of the complexes [DC-polarography and cyclic voltammetry (CV)] confirmed the existence and the nature of the metal ions in the chelate.     

Advanced oxidation processes for decolorization of aqueous solution containing acid red G azo dye

Some investigations concerning the decolorization of Acid Red G azo dye by photooxidation with hydrogen peroxide were performed. The influences of pH, oxidant concentration, and the presence of Fe²⁺ or other metal ions (Co²⁺, Cu²⁺, Ni²⁺, Mn²⁺) as potential catalysts, were investigated. The best results were obtained in the presence of ferrous ions in acid and neutral media. The other ions are not as effective as Fe²⁺ for dye decolorization. Co²⁺ and Cu²⁺ ions have a catalytic action, at low concentration, within a wide range of pH. Ni²⁺ and Mn²⁺ ions have no catalytic effect in photooxidation with hydrogen peroxide at acid Ni²⁺ and Mn²⁺ ions have no catalytic effect in photooxidation with hydrogen peroxide at acid pH values, but show a weak action in alkaline media.     

Synthesis and characterization of 2-(5-Bromo-2-Pyridylazo)-5-[(N,N-dicarboxylmethyl) amino]- phenol as a water-soluble chromogenic reagent

A new water soluble chromogenic reagent, 2-(5-bromo-pyridylazo)-5-[(N,N-dicarboxylmethyl)amino]-phenol has been synthesized. Its colour reaction with various metal ions was tested, and the acid dissociation constant of the reagent, and the stability constants of the chelates of Ni²⁺, Co²⁺, Cu²⁺, Mn²⁺, Pb²⁺, Zn²⁺ and UO ₂ ²⁺ were determined. The application of the reagent to spectrophotometric determination of nickel in irons is presented.     

Synthesis of a Dithiocarbamate Chelate Resin and Its Oxidized form and Their Adsorption Properties for Heavy Metal Ions

A series of macroporous dithiocarbamate chelate resins, III and V, and an oxidized resin, VI, with high adsorption capacity were prepared. The influence of various reaction conditions of amination, dithiocarboxylation, and oxidation were examined. The structure and the conversion of functional groups of resins were confirmed by IR spectra and elemental analysis. The adsorption capacities of Resin II for Hg²⁺, Cu²⁺, Zn²⁺, and Cd²⁺ are 4.40, 2.44, 1.77, and 1.36 mmol/g, respectively. The adsorption capacities of Resins V and VI for Cu²⁺. Zn²⁺, Ni²⁺, Co³⁺, Ag⁺, Hg²⁺, Cd²⁺, Pb²⁺, and Au³⁺ are 4.07–0.51 and 3.81–0.59 meq ion/g, respectively. The adsorption rate and the influence of pH on the adsorption percentage of the resins for metal ions were examined. Noble metal, transitional metal, and heavy metal ions can be quantitatively adsorbed by the resins. The adsorbed Cu²⁺, Pb²⁺, Cd²⁺, Co³⁺, and Ni²⁺ can be quantitatively eluted with 5N HNO₃, and the presence of large amounts of Ca²⁺, Mg²⁺, Fe³⁺, and Al³⁺ did not interfere.     

Study on Determination of Trace Nickel in Water Samples after Separation/enrichment using Microcrystalline Phenolphthalein Loaded with Chelate

The paper presents a novel method for the separation/enrichment of trace Ni²⁺ using microcrystalline phenolphthalein loaded with chelate prior to the determination by spectrophotometry. The effects of different parameters, such as the dosages of phenolphthalein and sodium diethyldithiocarbamate (DDTC), various salts and acidity on the enrichment yield of Ni²⁺ have been investigated to select the experimental conditions. The possible enrichment mechanism of Ni²⁺ was discussed. The results showed that under the optimum conditions, Ni²⁺ could be quantificationally adsorbed on the surface of microcrystalline phenolphthalein in the form of the chelate precipitate of Ni(DDTC)₂, while K⁺, Na⁺, Ca²⁺, Mg²⁺, Zn²⁺, Fe²⁺, Al²⁺, Pb²⁺ and Cd²⁺ could not be adsorbed at all. Therefore, Ni²⁺ was completely separated from the above metal ions in the solution. A new method for the separation/enrichment and determination of trace nickel using microcrystalline phenolphthalein loaded with chelate was established. The proposed method has been successfully applied to the determination of Ni²⁺ in various water samples, and the results agreed well with those obtained by FAAS method.     

Transport of metal ions through cation exchange membranes containing episulfide (or thiol) groups and/or triethylenetetramine side chains

Two types of cation exchange membranes bearing sulfonic acid groups were prepared. One membrane (EA membrane), having episulfide groups beside sulfonic acid groups, was prepared with 2,3-epithiopropylmethacrylate (ETMA)-2-acrylamide-2-methylpropane sulfonic acid (AMPS) copolymers and the another one (EA-TTA membrane) having thiol groups, triethylenetetramide (TTA) side chains, and carboxyl groups beside sulfonic acid groups was prepared by treating EA membranes with TTA in a water-1,4-dioxane mixture solution. The transport of metal ions such as K⁺, Li⁺, Ag⁺, Ca²⁺, and Cu²⁺ through the membranes was investigated. The transport rate of Ag⁺ through the EA membranes was considerably lower than those of other metal ions from solution. High selective transport of Ag⁺ from mixed solution could be observed using the EA and EA-TTA membranes. Transport of Cu²⁺ and Ca²⁺ through the EA-TTA membrane was depressed by an electrostatic repulsion between ammonium groups in the membranes and metal ions when HNO₃ or sodium ethylenediamine tetraacetate was used as receiving solution.     

Transition metal complexes of N-picolyl polyurethane

N-Picolyl polyurethanes (PUPY) were synthesized by nucleophilic substitution. The blends of these polyurethanes with various of transition metal chlorides [cobalt(II), nickel(II), and copper(II)] were studied by spectroscopic and thermal analysis. Ultraviolet-visible and infrared spectroscopic evidence indicates that a tetrahedral cobalt(II) complex with two pendent picolyl groups in the first-shell coordination sphere of Co²⁺ is formed in a series of blends with different molar ratio (from 10/1 to 2/1) of picolyl groups to cobalt(II) ions. According to the result of Small-Angle X-ray Scattering (SAXS), Differential Scanning Calorimetry (DSC), and Dynamic Mechanical Thermal Analysis (DMTA), coordination interaction between ligands in hard segments and metal ions provides a driving force for phase separation. The coordination strength of pyridine with Ni²⁺ is stronger than Co²⁺ and Cu²⁺. © 1998 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 36: 1539–1546, 1998     

Coordination Polymers. 9. Chelate Polymers Derived from Bisphenolic Complexes and Propylenediamine

Chelate polymers derived from bis(2,4-dihydroxybenzaldehyde)propyl-enediimine M and bis(2,4-dihydroxyacetophenone)propylenediimine M (M = Fe²⁺, Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺) with aromatic acid chlorides were prepared by interfacial polycondensation. Also, chelate polysiloxanes were obtained from the same monomers and α,ω-dichloropolydimethyl-siloxane. The spectral, thermal, magnetic, and electrical properties of the polychelates were studied.     

Separation and Recovery of Some Metal Ions Using Pan Sorbed Zinc Silicate as Chelating Ion Exchanger

Abstract

A new inorganic ion exchanger zinc silicate has been synthesized. Its properties such as ion exchange capacity, heat effect and stability etc. have been studied. Sorption of PAN over zinc silicate formed a chelate ion exchanger which showed greater selectivity for some metal ions especially for Cu²⁺, Ni²⁺, Co²⁺, Fe³⁺, Ag⁺, Ag³⁺ and Pt⁴⁺. Selectivity has been determined on the basis of distribution coefficients of these metal ions. Separations of Pt(IV) from Fe(III), Au(III) from Fe(III), Ag(I) from Cu(II) and Au(III) from Cu(II) have been reported. The recovery of Pt(IV) and Au(III) from dilute solutions has also been studied.