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chelation
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Synthesis of bridged bithiazoles
, Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 19, Issue 2 , 2000 , Pages 65-66 ; 10219986 (ISSN) ; Sharif University of Technology
2000
Abstract
Bridged bithiazoles (5,5′-ethylene-4,4′-bithiazoles) are synthesized as a good chelating agent
Comments on the " A comparative study of chelating and cationic ion exchange resins for the removal of palladium (II) complexes from acidic chloride media"
, Article Journal of Hazardous Materials ; Volume 229-230 , 2012 , Pages 461-462 ; 03043894 (ISSN) ; Khanchi, A. R ; Outokesh, M ; Tayebi, A ; Sharif University of TechnologyOrganoplatinum(ii) complexes containing chelating or bridging bis(N-heterocyclic carbene) ligands: Formation of a platinum(ii) carbonate complex by aerial CO2 fixation
, Article Dalton Transactions ; Volume 40, Issue 37 , Jun , 2011 , Pages 9362-9365 ; 14779226 (ISSN) ; Milić, D ; Kia, R ; Mazloomi, Z ; Abdolahi, H ; Sharif University of Technology
2011
Abstract
The preparation of two new bis(N-heterocyclic carbene) platinum(ii) complexes, in which NHC rings are joined by a CH2 linker group, is described. While, the chelate complex [PtMe2(bis-NHC1)], 1, was formed with large tert-butyl wingtips, the iso-propyl N-substituent analogue favors formation of the cluster complex [Pt2Me4(μ- SMe2)(μ-bis-NHC2)]2(μ-Ag2Br2), 2, in which two binuclear platinum(ii) complexes are linked together by an Ag2Br2 unit. The chelating platinum complex 1 undergoes aerial CO2 fixation and forms platinum(ii) carbonate complex [Pt(CO3)(bis-NHC1)], 3
Comparison of the batch and breakthrough properties of stable and plain alginate microcapsules with a chelating resin and an ion exchanger in Ag+ adsorption
, Article Industrial and Engineering Chemistry Research ; Volume 47, Issue 17 , 5 August , 2008 , Pages 6742-6752 ; 08885885 (ISSN) ; Niibori, Y ; Mimura, H ; Ahmadi, S. J ; Sharif University of Technology
2008
Abstract
A comparative study on the uptake properties of alginate microcapsules containing Cyanex 302 extractant, Lewatite TP 214 chelating resin, and Amberlite 200CT strongly acidic ion exchanger has been conducted using Ag+ as the target ion. The study resulted in an analytical formula, as well as three phenomenological breakthrough formulas that are also applicable in other fixed-bed operations. It also demonstrated a close similarity of the uptake properties of alginate microcapsules (MCs) and the chelating resins. Advantages of MCs over chelating resins include ease of preparation, ability to immobilize different extractants, and, most remarkably, an enormous distribution factor (Kd ≈ 106...
The Effect of Metal Ion Chelation on Formation of Perovskite Versus Perovskite-Related Compounds and The Study of Their Photocatalytic Activity
, M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram (Supervisor)
Abstract
In this study, effect of chelate ligands containing carboxylic, phenolic, and amine functional groups on the synthesis of related-perovskite Ca2Fe2O5 versus perovskite CaFeO3 structures have been investigated. Herein, the application of chelating-agent method, e.g. EDTA, Citric Acid, NTA, malonic acid, maleic acid, catechol, acetylaceton, p-tert-butycatechol, aminophenolic derivative ligand, and 2-hydroxyiminodiacetic acid, in comparison to co-precipitation method was also undertaken. The crystalline structure of the obtained perovskites were compared with those of co-participation method in solid state. Experimentally, it was found that the related XRD bands for CaFeO3 were appeared in the...
Designing a new multifunctional peptide for metal chelation and Aβ inhibition
, Article Archives of Biochemistry and Biophysics ; Volume 653 , 2018 , Pages 1-9 ; 00039861 (ISSN) ; Asadbegi, M ; Khandan, V ; Amanzadi, A ; Sharif University of Technology
Academic Press Inc
2018
Abstract
According to the Amyloid hypothesis, as the foremost scientific explanation for Alzheimer Disease (AD), the neuropathology of AD is related to toxic fragments of amyloid beta (Aβ) protein. Based on this hypothesis, an attractive therapeutic approach was demonstrated to identify multifunctional peptides able to modulate Aβ pathologies as the source of AD. On this premise, a bifunctional polypeptide based on the iAβ5p lead compound, was designed to inhibit Aβ aggregation and free metal ions. Herein, the efficacy of this novel drug in Zn2+ and Cd2+ ion chelation was examined through an integrated technique comprising combined Docking, QM, and MD simulations. MD relaxation of a set of probable...
Comparison of oxygen permeation through some perovskite membranes synthesized with EDTNAD
, Article Reaction Kinetics, Mechanisms and Catalysis ; Volume 100, Issue 2 , August , 2010 , Pages 459-469 ; 18785190 (ISSN) ; Nazari, K ; Seyed Matin, N ; Safekordi, A. A ; Ghanbari, B ; Zarrinpashne, S ; Ahmadi, R ; Sharif University of Technology
Abstract
Three dense membranes of types SrCo0.8Fe0.2O 3-δ (SCF(82)), La0.6Sr0.4Co 0.8Fe0.2O3-δ (LSCF(6482)) and La 0.8Sr0.2Co0.6Fe0.4O 3-δ (LSCF(8264)) perovskites were prepared by complexation applying a chelating agent, ethylene diamine N,N,N′,N′-tetra-N- acetyl-diamine (EDTNAD). The oxygen permeation flux through the perovskite membranes was measured as a function of temperature within 1,073-1,223 K as well as the oxygen partial pressure of 0.1-1.0 bar. The oxygen permeation fluxes for the membranes, SCF(82), LSCF(6482), LSCF(8264) with the thickness of 0.85 mm were observed as 9.2×10-7 (mol/cm2 s), 1.7×10-7 (mol/cm2 s), and 1.0×10-7 (mol/cm2 s) in these cases at 1,153 K. The results indicated the...
Sol-gel synthesis of Mn1.5Co1.5O4 spinel nano powders for coating applications
, Article Materials Research Bulletin ; Volume 102 , 2018 , Pages 180-185 ; 00255408 (ISSN) ; Dayaghi, A. M ; Askari, M ; Gannon, P. E ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
Mn1.5Co1.5O4 oxide spinels are widely used as protective coatings for stainless steel interconnects within planar solid oxide fuel cell stacks. Containing both cubic and tetragonal crystalline phases, these Mn/Co oxide spinels exhibit favorable thermal stability and electronic conductivity for the SOFC interconnect application. Slurry-based coating applications of Mn/Co oxides require precursor powders, which can benefit from being nano-structured. In this study, the sol-gel synthesis of nanocrystalline Mn1.5Co1.5O4 spinel is investigated. The decomposition of sol-gel precursors, as well as the crystalline phase structures and microstructures of the product Mn1.5Co1.5O4 are characterized by...
Synthesis and characterization of LiNiO2 nanopowder with various chelating agents
, Article Journal of Nanomaterials ; Volume 2010 , March , 2010 ; 16874110 (ISSN) ; Asgari, S ; Sharif University of Technology
2010
Abstract
LiNiO2 powders were synthesized with acrylic acid, citric acid, oxalic acid, and triethanolamine (TEA) as a chelating agent. Crystallized LiNiO2 was synthesized in air at a calcinations temperature of 500 °C for 12 hours, when the molar ratio of chelating agents to total metal ion (RPM) was 1.0. The TEA-assisted method had the highest intensity ratio of (003)/(104) peaks of X-ray diffraction (XRD) spectrum. The transmission electron microscopy (TEM) analysis indicates that the sample prepared with triethanolamine obtained the smallest particle size with average particle size of only 12nm. The results indicate that chelating agents have an important role in the intensity ratio of (003)/(104)...
Novel salep-based chelating hydrogel for heavy metal removal from aqueous solutions
, Article Polymers for Advanced Technologies ; Volume 27, Issue 8 , 2016 , Pages 999-1005 ; 10427147 (ISSN) ; Pourjavadi, A ; Monfared, A ; Khorasani, Z ; Sharif University of Technology
John Wiley and Sons Ltd
Abstract
A novel optimized chelating hydrogel was synthesized via graft copolymerization of acrylamide and 2-hydroxyethyl methacrylate (as two-dentate chelating co-monomer) onto salep (a multicomponent polysaccharide obtained from dried tubers of certain natural terrestrial orchids) using N,N′-methylenebisacrylamide as a crosslinker and ammonium persulfate as an initiator. Reaction parameters (N,N′-methylenebisacrylamide and ammonium persulfate amounts as well as acrylamide/2-hydroxyethyl methacrylate weight ratio) affecting the water absorption of the chelating hydrogel were optimized using a systematic method to achieve a hydrogel with high swelling capacity as possible. Heavy metal ion adsorption...
Identification of a novel multifunctional ligand for simultaneous inhibition of amyloid-beta (aβ42) and chelation of zinc metal ion
, Article ACS Chemical Neuroscience ; Volume 10, Issue 11 , 2019 , Pages 4619-4632 ; 19487193 (ISSN) ; Shamloo, A ; Sharif University of Technology
American Chemical Society
2019
Abstract
Zinc binding to β-amyloid structure could promote amyloid-β aggregation, as well as reactive oxygen species (ROS) production, as suggested in many experimental and theoretical studies. Therefore, the introduction of multifunctional drugs capable of chelating zinc metal ion and inhibiting Aβ aggregation is a promising strategy in the development of AD treatment. The present study has evaluated the efficacy of a new bifunctional peptide drug using molecular docking and molecular dynamics (MD) simulations. This drug comprises two different domains, an inhibitor domain, obtained from the C-terminal hydrophobic region of Aβ, and a Zn2+ chelating domain, derived from rapeseed meal, merge with a...
Investigation of Amyloid-Beta Inhibition using Multifunctional Peptide Drugs Associated with Metal Ions
, Ph.D. Dissertation Sharif University of Technology ; Shamloo, Amir (Supervisor)
Abstract
Many experimental and theoretical studies have suggested that zinc binding to Aβ could promote amyloid-β aggregation and reactive oxygen species (ROS) production induced by AD disease. Therefore, the introduction of multifunctional drugs capable of chelating zinc metal ion and inhibiting Aβ aggregation is a promising strategy in the development of AD treatment. In present study molecular docking and molecular dynamics (MD) simulations were used to evaluate the efficacy of two new bifunctional peptide drug, composed of two different domains: C-terminal hydrophobic region of Aβ and Zn2+ chelator region. To evaluate the multifunctionality of the ligands, a comprehensive set of MD simulations up...
Synthesis, structure and photophysical properties of binuclear methylplatinum complexes containing cyclometalating 2-phenylpyridine or benzo{h}quinoline ligands: A comparison of intramolecular Pt-Pt and π-π Interactions
, Article Dalton Transactions ; Volume 40, Issue 36 , 2011 , Pages 9123-9130 ; 14779226 (ISSN) ; Czerwieniec, R ; Kia, R ; Jamshidi, Z ; Zabel, M ; Sharif University of Technology
2011
Abstract
The binuclear cyclometalated complexes [Pt2Me 2(ppy)2(μ-dppm)], 1a, and [Pt2Me 2(bhq)2(μ-dppm)], 1b, in which ppy = 2-phenylpyridyl, bhq = benzo{h}quinoline and dppm = bis(diphenylphosphino)methane, were synthesized by the reaction of [PtMe(SMe2)(ppy)] or [PtMe(SMe 2)(bhq)] with 1/2 equiv of dppm at room temperature, respectively. Complexes 1a and 1b were fully characterized by multinuclear (1H, 31P, 13C, and 195Pt) NMR spectroscopy and were further identified by single crystal X-ray structure determination. A comparison of the intramolecular Pt-Pt and π-π interactions in complexes 1a and 1b has been made on the basis of data on crystal structures and wave functions analysis. The binuclear...
An ultrasensitive and selective turn-off fluorescent nanoprobe for the detection of copper ions
, Article Analytical Methods ; Volume 7, Issue 12 , 2015 , Pages 5067-5073 ; 17599660 (ISSN) ; Taghipour, M ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
In this study, a novel approach for sensitive and extremely selective detection of copper ions has been developed based on fluorescence resonance energy transfer (FRET) between AuNPs as an acceptor and fluorescein isothiocyanate (FITC) as a donor. Initially, the fluorescence of the FITC molecule turns-off due to adsorption to the AuNPs surface. However, the fluorescence of the FITC-AuNPs system was switched to turn-on by adding d-Pencillamine (d-PC) to the solution mixtures as FITC molecules are released upon displacement by d-PC on the NPs surface. The higher affinity of d-PC toward the surface of AuNPs was further evidenced by controlling the fluorescence intensity enhancement of the...
Nano cobalt ferrite catalyzed coupling reaction of nitroarene and alkyl halide: An odorless and ligand-free rout to unsymmetrical thioether synthesis
, Article Catalysis Communications ; Volume 94 , 2017 , Pages 33-37 ; 15667367 (ISSN) ; Pourkaveh, R ; Sharif University of Technology
Elsevier B.V
2017
Abstract
This study describes an odorless protocol for the synthesis of unsymmetrical sulfides via cobalt ferrite (CoFe2O4) catalyzed cross-coupling reaction of nitroarenes with alkyl halides in the presence of thiourea as sulfur source under ligand-free conditions. The catalyst was recycled using external magnetic field and reused for ten consecutive runs in the reaction of nitrobenzene, thiourea and benzyl bromide without significant loss of activity. Apart from being magnetically separable, being inexpensive and air-stable are another important features of this catalytic system. All the products were formed in good yields and short reaction times. © 2017 Elsevier B.V
Turn-off chelation-enhanced fluorescence sensing of carbon dot-metallic deep eutectic solvent by imidazole-based small molecules
, Article Sensors and Actuators B: Chemical ; Volume 344 , 2021 ; 09254005 (ISSN) ; Bagheri, H ; Es-haghi, A ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Low accuracy, requirement of expensive instruments, derivatization and multi-step sample preparation, inconsistencies during the fabrication process, time-consuming procedures and utilization of eco-unfriendly chemicals are some limitations of various developed methods for detection of 4-methylimidazol (4-MeI). Herein, a rapid and miniaturized fluorescent probe based on the ultrasound‒assisted formation of carbon dots (CDs) in a metallic deep eutectic solvent (MDES) was developed and conveniently implemented to detect 4-MeI in commercial dark soft drinks. In-situ synthesis of CDs-chelated metals in the presence of the target analyte facilitates a kinetically fluorescence emission with no...
Metal-Organic cubane cage with trimethylplatinum(IV) vertices
, Article Inorganic Chemistry ; Volume 61, Issue 1 , 2022 , Pages 15-19 ; 00201669 (ISSN) ; Jamali, S ; Mahmoudi, S ; Samouei, H ; Nayeri, S ; Chabok, S. M. J ; Jamshidi, Z ; Sharif University of Technology
American Chemical Society
2022
Abstract
Herein we describe the synthesis and characterization of the first platinum(IV) metal-organic cage [(Me3PtIV)8(byp)12](OTf)8 (2), in which the organometallic moieties trimethylplatinum(IV) (PtMe3) occupied the corners of a cubane structure and 4,4′-bipyridine ligands used as linkers. The first-principles density functional theory calculations showed that the highest occupied molecular orbitals were localized on the PtMe3 moieties, while the lowest unoccupied molecular orbitals were distributed on the organic linkers. © 2021 American Chemical Society
Synthesis and electrochemical properties of LiNi0.8Co 0.2O2 nanopowders for lithium ion battery applications
, Article Journal of Power Sources ; Volume 196, Issue 1 , 2011 , Pages 337-342 ; 03787753 (ISSN) ; Asgari, S ; Sharif University of Technology
Abstract
Nitrates of lithium, cobalt and nickel are utilized to synthesize LiNi 0.8Co0.2O2 cathode material through sol-gel technique. Various synthesis parameters such as calcination time and temperature as well as chelating agent are studied to determine the optimized condition for material processing. Using TG/DTA techniques, the optimized calcination temperatures are selected. Different characterization techniques such as ICP, XRD and TEM are employed to characterize the chemical composition, crystal structure, size and morphology of the powders. Micron and nano-sized powders are produced using citric/oxalic and TEA as chelating agent, respectively. Selected powders are used as cathode material...
Characterization of LiCoO2 nanopowders produced by sol-gel processing
, Article Journal of Nanomaterials ; Volume 2010 , 2010 ; 16874110 (ISSN) ; Soltanmohammad, S ; Sharif University of Technology
2010
Abstract
LiCoO2 nanopowders, one of the most important cathode materials for lithium-ion batteries, were synthesized via a modified sol-gel process assisted with triethanolamine (TEA) as a complexing agent. The influence of three different chelating agents including acrylic acid, citric acid, and oxalic acid on the size and morphology of particles was investigated. Structure and morphology of the synthesized powders were characterized by thermogravimetric/ differential thermal analyses (TG/DTA), X-ray diffraction (XRD), and transmission electron microscopy (TEM). Results indicate that the powder processed with TEA and calcinated at 800 °C had an excellent hexagonal ordering of α-NaFeO2 -type (space...
An improved synthesis and preliminary biodistribution study of a technetium-99m-labeled2-amino-2-deoxy(thioacetyl)-D-glucose complex ([ 99mTc]-TA-DG) as a tumor imaging agent
, Article Iranian Journal of Nuclear Medicine ; Volume 15, Issue 28 , 2007 , Pages 43-48 ; 16812824 (ISSN) ; Sadeghzadeh, M ; Charkhlooie, G ; Haghir Ebrahimabadi, K ; Saeedi, M. R ; Sharif University of Technology
2007
Abstract
Introduction: This report describes the synthesis of 2-Amino-2-deoxy(S- benzoylthioacetyl)-D-glucose (S-Bz-TA-DG), radiolabeled with [ 99mTc(CO)3(OH2)3]+ complex with a procedure including deprotection of the benzoyl group, characterization by HPLC using a C18 reverse phase column and preliminary biodistribution study in normal mice. Methods: [99mTc(CO) 3(H2O)3]+ complex was used to label TA-DG with 99mTc. This complex was prepared using up to 46 mCi of Na99mTcO4 in 1mL saline. The radiochemical purity (>95%) was determined by TLC in normal saline solution as the mobile phase. Radio-HPLC analysis of [99mTc]-(TA-DG) at pH=9.5-10, revealed that labeling with 99mTc resulted in the formation of...