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Cold atmospheric plasma modification and electrical conductivity induction in gelatin/polyvinylidene fluoride nanofibers for neural tissue engineering
, Article Artificial Organs ; Volume 46, Issue 8 , 2022 , Pages 1504-1521 ; 0160564X (ISSN) ; Hosseini, E ; Ramazani Saadatabadi, A ; Atyabi, S ; Bakhshandeh, H ; Mohamadali, M ; Aidun, A ; Farasati Far, B ; Sharif University of Technology
John Wiley and Sons Inc
2022
Abstract
Background: This research follows some investigations through neural tissue engineering, including fabrication, surface treatment, and evaluation of novel self-stimuli conductive biocompatible and degradable nanocomposite scaffolds. Methods: Gelatin as a biobased material and polyvinylidene fluoride (PVDF) as a mechanical, electrical, and piezoelectric improvement agent were co-electrospun. In addition, polyaniline/graphene (PAG) nanoparticles were synthesized and added to gelatin solutions in different percentages to induce electrical conductivity. After obtaining optimum PAG percentage, cold atmospheric plasma (CAP) treatment was applied over the best samples by different plasma variable...
Co-doping a metal (Cr, Mn, Fe, Co, Ni, Cu, and Zn) on Mn/ZSM-5 catalyst and its effect on the catalytic reduction of nitrogen oxides with ammonia
, Article Research on Chemical Intermediates ; Volume 43, Issue 4 , 2017 , Pages 2143-2157 ; 09226168 (ISSN) ; Hamidzadeh, M ; Sharif University of Technology
Springer Netherlands
2017
Abstract
Selective catalytic reduction (SCR) of NOx by NH3 over a series of Mn–M/Z catalysts (M = Cr, Mn, Fe, Co, Ni, Cu, Zn, and Z = the ZSM-5 Zeolite) synthesized by wet impregnation method was investigated. Mn–Fe/Z, Mn–Co/Z, and Mn–Cu/Z catalysts exhibited approximately 100 % NOx conversion over a wide temperature range (200–360 °C) in a defined atmospheric condition, which was noticeably greater than that of Mn–Cr/Z (340–360 °C). Furthermore, the effect of addition of second metal oxide species to the initial Mn/Z catalyst on the structure of catalysts was studied by several characterization techniques. BET measurements revealed high surface area and pore volume of the Mn–Cu/Z catalyst. In...
COD and ammonia removal from landfill leachate by UV/PMS/Fe2+ process: ANN/RSM modeling and optimization
, Article Process Safety and Environmental Protection ; Volume 159 , 2022 , Pages 716-726 ; 09575820 (ISSN) ; Mozaffarian, M ; Dabir, B ; Ramezani, S. F ; Sharif University of Technology
Institution of Chemical Engineers
2022
Abstract
Landfill leachate is a highly contaminated liquid generated in municipal solid waste landfills. The application of sulfate radical-based advanced oxidation processes (SR-AOP) in landfill leachate treatments is emerging due to their ability to degrade both organic refractory matters and ammonia nitrogen. In this paper, application of peroxymonosulfate (PMS), activated by Fe2+ and UV was used as an economical and environmentally friendly approach for treatment of landfill leachate. Chemical oxygen demand (COD) and ammonia removals were measured as the two primary responses of landfill leachate to UV/PMS/Fe2+ treatment system. The main parameters (pH, PMS/Fe2+ mass ratio, Fe2+ dosage) affecting...
CO2/CH4 separation by mixed-matrix membranes holding functionalized NH2-MIL-101(Al) nanoparticles: Effect of amino-silane functionalization
, Article Chemical Engineering Research and Design ; Volume 176 , 2021 , Pages 49-59 ; 02638762 (ISSN) ; Ahmadijokani, F ; Molavi, H ; Rezakazemi, M ; Arjmand, M ; Sharif University of Technology
Institution of Chemical Engineers
2021
Abstract
In this study, NH2-MIL-101(Al) metal-organic frameworks (MOFs) covered with 3-aminopropyltriethoxysilane (APTES) were incorporated into the polyethersulfone (PES) to produce mixed-matrix membranes (MMMs) for CO2 separation. The APTES functionalization was performed to improve the MOF dispersion in the PES matrix. Different analyses such as X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and field emission scanning electron microscopy (FESEM) revealed that the MOFs surface successfully functionalized with APTES. An improvement in CO2/CH4 separation efficiency was observed in MMMs, and the performance...
CO2/CH4 separation by mixed-matrix membranes holding functionalized NH2-MIL-101(Al) nanoparticles: Effect of amino-silane functionalization
, Article Chemical Engineering Research and Design ; Volume 176 , 2021 , Pages 49-59 ; 02638762 (ISSN) ; Ahmadijokani, F ; Molavi, H ; Rezakazemi, M ; Arjmand, M ; Sharif University of Technology
Institution of Chemical Engineers
2021
Abstract
In this study, NH2-MIL-101(Al) metal-organic frameworks (MOFs) covered with 3-aminopropyltriethoxysilane (APTES) were incorporated into the polyethersulfone (PES) to produce mixed-matrix membranes (MMMs) for CO2 separation. The APTES functionalization was performed to improve the MOF dispersion in the PES matrix. Different analyses such as X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and field emission scanning electron microscopy (FESEM) revealed that the MOFs surface successfully functionalized with APTES. An improvement in CO2/CH4 separation efficiency was observed in MMMs, and the performance...
CMC-g-poly (sodium acrylate)/kaolin superabsorbent hydrogel composites: Synthesis, characterization and swelling behaviour
, Article Polymers and Polymer Composites ; Volume 14, Issue 7 , 2006 , Pages 701-712 ; 09673911 (ISSN) ; Ghasemzadeh, H ; Sharif University of Technology
Rapra Technology Ltd
2006
Abstract
A novel superabsorbent composite system based on carboxymethyl cellulose (CMC) was prepared by graft copolymerization of acrylic acid (AA) in the presence of kaolin powder using methylenebisacrylamide (MBA) as a crosslinking agent and ammonium persulfate (APS) as an initiator. The effect of reaction variables, such as MBA, AA, and APS concentration and CMC/kaolin ratio on the water absorbency of the composite were studied. Evidence of grafting and kaolin interaction was obtained by comparing the FT-IR spectra of the initial substrates with that of the superabsorbent composite. The results indicated that with increasing amount of kaolin, the swelling capacity was increased and then...
CMC/celite superabsorbent composites: Effect of reaction variables on saline-absorbency under load
, Article Iranian Polymer Journal (English Edition) ; Volume 19, Issue 8 , May , 2010 , Pages 571-579 ; 10261265 (ISSN) ; Soleyman, R. A ; Ghasemzadeh, H ; Salimi, H ; Sharif University of Technology
Abstract
A series of superabsorbent composites were synthesized through graft copolymerization of acrylic acid (AA) onto carboxymethyl cellulose (CMC) in the presence of celite powder using N,N'-methylenebisacrylamide (MBA) as a cross-linking agent and ammonium persulphate (APS) as an initiator. The chemical structure and thermal properties of the composite hydrogels were characterized by FTIR spectroscopy and TGA methods, respectively. Morphology of the samples was examined by scanning electron microscopy (SEM). In free-state, the swelling conditions and hence the related data are not real, because in all their applications the swelling particles of superabsorbent must absorb aqueous solutions while...
Chitosan-g-PLGA copolymer as a thermosensitive membrane
, Article Carbohydrate Polymers ; Volume 80, Issue 3 , 2010 , Pages 740-746 ; 01448617 (ISSN) ; Abdekhodaie, M. J ; Sharif University of Technology
2010
Abstract
A thermosensitive copolymer was synthesized by graft copolymerization of poly(lactide-co-glycolide) (PLGA) copolymers onto the surface of chitosan membranes. Acryloyl chloride was used as a coupling reagent for the covalent attachment of PLGA to the chitosan membranes. FTIR spectroscopy and DSC analysis were used to characterize the resulting graft copolymer. Thermosensitive swelling behaviors of the copolymer were investigated as well. The membranes exhibited reversible swelling-shrinking behavior; higher swelling ratios were obtained observed at higher temperatures. Drug permeation studies were carried out using vancomycin hydrochloride and betamethasone sodium phosphate as the model...
Chitosan-gelatin sheets as scaffolds for muscle tissue engineering
, Article Artificial Cells, Nanomedicine and Biotechnology ; Volume 43, Issue 2 , Nov , 2015 , Pages 124-132 ; 21691401 (ISSN) ; Mashayekhan, S ; Nazaripouya, A ; Naji, M ; Hunkeler, D ; Rajabi Zeleti, S ; Sharifiaghdas, F ; Sharif University of Technology
Informa Healthcare
2015
Abstract
Hydrogels made of natural polymers [chitosan (CS) and gelatin (G)] have been prepared having mechanical properties similar to those of muscle tissues. In this study, the effect of polymer concentration and scaffold stiffness on the behavior of seeded muscle-derived cells (MDCs) on the CS-G hydrogel sheets has been evaluated. Both variables were found to be important in cell viability. Viability was assessed by observation of the cell morphology after 1 day as well as a 14-day MTT assay. The CS-G hydrogels were characterized using Fourier transform infrared (FTIR) analysis, which revealed evidences of strong intermolecular interactions between CS and G. Hydrogel samples with intermediate...
Chemo-physical properties of renal capsules under ultraviolet-c exposure
, Article Journal of Applied Physics ; Vol. 116, Issue. 5 , 2014 ; ISSN: 00218979 ; Parvin, P ; Reyhani, A ; Mortazavi, S. Z ; Mokhtari, S ; Amjadi, A ; Sharif University of Technology
Abstract
The renal capsule tissue of lamb was irradiated with ultraviolet-C light and the treated samples were analyzed by uniaxial tensile test, dynamic mechanical analysis, attenuated total reflectance Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and contact angle measurements. It was shown that the skin cross-linking is dominant in low doses in accordance with the contact angle assessment. Conversely, the strong bulk degradation takes place at high doses. Similarly, the bulk cross-linking affects the mechanical tests as to enhance the stiffness at low doses, whereas strong degradation occurs at high doses that mainly arises from the strong bulk chain scission
Characterization of sol-gel derived silver/fluor-hydroxyapatite composite coatings on titanium substrate
, Article Surface and Coatings Technology ; Volume 352 , 2018 , Pages 522-528 ; 02578972 (ISSN) ; Abbasi Khazaei, B ; Afshar, A ; Sharif University of Technology
Elsevier B.V
2018
Abstract
A composite coating containing silver, fluoride and hydroxyapatite (Ag-FHA) was developed on titanium substrate by sol-gel method. Triethylphosphite, hydrated calcium nitrate, ammonium fluoride and silver nitrate were used respectively, as P, Ca, F and Ag precursors with a Ca:P ratio 1.67 and concentration of silver was 0.3 wt%. Coatings were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) and atomic absorption spectrometry (AAS). Potentiodynamic polarization measurements in simulated body fluid proved corrosion protection caused by both Ag-FHA coatings. Antibacterial activity of coatings against...
Characterisation of nanocrystalline sulfated titania modified with transition metals and aluminum as solid acids for esterification
, Article Progress in Reaction Kinetics and Mechanism ; Volume 41, Issue 1 , 2016 , Pages 57-66 ; 14686783 (ISSN) ; Abolhasani, E ; Ghasemi, S ; Sharif University of Technology
Science Reviews 2000 Ltd
2016
Abstract
TiO2, transition metal (Cr, Mn, Fe, Co, Ni, Cu, and Zn)- and aluminum-doped TiO2 nanoparticles were prepared by the sol-gel technique. The sulfated catalysts were prepared by the impregnation method with H2SO4 solution. The catalysts were characterised by X-ray diffraction (XRD), BET surface area measurement, diffuse reflectance spectroscopy (DRS), and Fourier transform infrared (FTIR) techniques. The sulfate content of the metal-incorporated samples was considerably higher than for SO4 2-/TiO2. The metal doping brought about a considerable reduction in the extent of sulfate loss from the catalyst surface due to the wide dispersion on the surface. The SO4 2-/TiO2 and SO4 2-/M/TiO2...
Catechin mediated green synthesis of Au nanoparticles: Experimental and theoretical approaches to the determination HOMO-LUMO energy gap and reactivity indexes for the (+)-epicatechin (2S, 3S)
, Article Arabian Journal of Chemistry ; Volume 15, Issue 5 , 2022 ; 18785352 (ISSN) ; Khayatkashani, M ; Soltani, N ; Yousif, Q. A ; Salavati Niasari, M ; Sharif University of Technology
Elsevier B.V
2022
Abstract
This work suggests a green method for synthesizing Au nanoparticles (AuNPs) using the aqueous extract of Salix aegyptiaca extract. The mechanism of green synthesized AuNPs was examined by molecular electrostatic potential (MEP) calculations. AuNPs were characterized with different techniques such as Ultraviolet–visible spectroscopy (UV–vis), Fourier-transform infrared spectroscopy (FT-IR) spectroscopy, X-ray diffraction (XRD), and Transmission electron microscopy (TEM). Electrochemical investigation of modified glassy carbon electrode using AuNPs (AuNPs/GCE) shows that the electronic transmission rate between the modified electrode and [Fe (CN)6]3−/4− increased. Process of oxidation, energy...
Catalytic and antibacterial properties of 3-dentate carboxamide Pd/Pt complexes obtained via a benign route
, Article Applied Organometallic Chemistry ; Volume 34, Issue 4 , April , 2020 ; Bagherzadeh, M ; Meghdadi, S ; Fadaei Tirani, F ; Schenk Joß, K ; Rabiee, N ; Sharif University of Technology
John Wiley and Sons Ltd
2020
Abstract
The complexes PdII(qcq)(OAc) and PtII(qcq)Cl have been synthesized using environmentally benign synthesized ligands and characterized by elemental analyses: Fourier transform infrared spectroscopy, UV–visible spectroscopy, 1H NMR spectroscopy, and X-ray diffraction. The catalytic activity of the complex was assessed, in different media, for the Mizoroki–Heck coupling reaction for typical aryl halides and terminal olefins under aerobic conditions. Since the base and the solvent were found to influence the efficiency of the reaction, reaction conditions, temperature, time, and the amount of K3PO4 and a mixture of H2O/PEG, were optimized. We found, for the Mizoroki–Heck reaction coupling less...
Carrageenan-g-poly(acrylamide)/poly(vinylsulfonic acid, sodium salt) as a novel semi-IPN hydrogel: Synthesis, characterization, and swelling behavior
, Article Polymer Engineering and Science ; Volume 47, Issue 9 , 2007 , Pages 1388-1395 ; 00323888 (ISSN) ; Ghasemzadeh, H ; Sharif University of Technology
2007
Abstract
A semi-interpenetrating polymer network (semi-IPN) hydrogel based on kappa-carrageenan (κC) and poly (vinylsulfonic acid, sodium salt) (PVSA) was prepared by graft copolymerization of acrylamide (AAm) using methylenebisacrylamide (MBA) as a crosslinking agent and ammonium persulfate (APS) as an initiator. FTIR spectroscopy was used for confirming the structure of the final product. It was found that the chemical composition of the Semi-IPN hydrogel is equal to the initial homopolymers and monomer feed compositions. The swelling capacity of the hydrogel was shown to be affected by the MBA, APS, and AAm concentration as well as κC/PVSA weight ratio. The swelling behavior of the hydrogel was...
Carbon-based nanocomposite decorated with bioactive glass and CoNi2S4 nanoparticles with potential for bone tissue engineering
, Article OpenNano ; Volume 8 , 2022 ; 23529520 (ISSN) ; Aldhaher, A ; Ahmadi, S ; Baheiraei, N ; Rabiee, N ; Sharif University of Technology
Elsevier Inc
2022
Abstract
In this work, for the first time, different forms of nanocomposites based on rGO and MWCNT were prepared in conjoining with the bioactive glass (BioGlass). In the carbonic layers, a highly toxic nanoparticle, CoNi2S4, was intercalated, and the role of this nanoparticle in the alkaline phosphatase activity, relative cell viability on different cell lines, and also the effect on the cell walls and cell morphologies were investigated. From another perspective, the ability of the chemotherapy drug loading to the prepared nanocomposites was investigated, and the use of leaf extracts was thought of as a green method to lower the cytotoxicity and regulate the genotoxicity of the generated...
Bottom-up synthesis of nitrogen and oxygen co-decorated carbon quantum dots with enhanced DNA plasmid expression
, Article Colloids and Surfaces B: Biointerfaces ; Volume 184 , 2019 ; 09277765 (ISSN) ; Khezri, J ; Esfandiari, S ; Mahdavi, H ; Karkhane, A. A ; Rahighi, R ; Heidarimoghadam, R ; Tayebi, L ; Hashemi, E ; Farmany, A ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In this paper, a bottom-up hydrothermal route is reported for the synthesis of oxygen and nitrogen co-decorated carbon quantum dots (CQDs) using ammonium hydrogen citrate (AHC) as a single precursor. DLS data approved the formation of 4.0 nm (average size) CQDs. XRD pattern shows the interlayer spacing (002) of 3.5 Å for CQDs, which is exactly the same as that of crystalline graphite. XPS and FTIR spectra verified the formation of oxygen and nitrogen functional groups on the CQDs surface. Co-decorated carboxyl, hydroxyl and amine groups on the CQDs surfaces make them as promising polyelectrolyte for gene delivery. Toxicity assay showed a survival rate of 70% under different incubation times...
Both tough and soft double network hydrogel nanocomposite based on o-carboxymethyl chitosan/poly(vinyl alcohol) and graphene oxide: a promising alternative for tissue engineering
, Article Polymer Engineering and Science ; Volume 60, Issue 5 , 2020 , Pages 889-899 ; Mazaheri Tehrani, Z ; Salami, H ; Seidi, F ; Motamedi, A ; Amanzadi, A ; Zayerzadeh, E ; Shabanian, M ; Sharif University of Technology
John Wiley and Sons Inc
2020
Abstract
A reinforced double network (DN) hydrogel as a candidate for skin scaffold was prepared. It consists of O-carboxymethyl chitosan, polyvinyl alcohol, honey, CaCl2, and graphene oxide. The various concentrations of CaCl2, namely, 30, 45, and 60 wt% were investigated. Besides, the GO content was studied as 3, 5, and 10 wt%. The structure of the DN was characterized by Fourier-transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, X-ray diffraction, energy dispersive X-ray and Brunauer-Emmett-Teller were evaluated. The mechanical properties were studied, too. It showed that the DN with 45 wt% CaCl2 was optimized. Also, swelling mechanism was investigated....
Biomimetic proteoglycan nanoparticles for growth factor immobilization and delivery
, Article Biomaterials Science ; Volume 8, Issue 4 , 2020 , Pages 1127-1136 ; Mostafavi, E ; Shokrgozar, M. A ; Tamjid, E ; Webster, T. J ; Annabi, N ; Simchi, A ; Sharif University of Technology
Royal Society of Chemistry
2020
Abstract
The delivery of growth factors is often challenging due to their short half-life, low stability, and rapid deactivation. In native tissues, the sulfated residual of glycosaminoglycan (GAG) polymer chains of proteoglycans immobilizes growth factors through the proteoglycans'/proteins' complexation with nanoscale organization. These biological assemblies can influence growth factor-cell surface receptor interactions, cell differentiation, cell-cell signaling, and mechanical properties of the tissues. Here, we introduce a facile procedure to prepare novel biomimetic proteoglycan nanocarriers, based on naturally derived polymers, for the immobilization and controlled release of growth factors....
Biomimetic apatite layer formation on a novel citrate starch scaffold suitable for bone tissue engineering applications
, Article Starch/Staerke ; Volume 68, Issue 11-12 , 2016 , Pages 1275-1281 ; 00389056 (ISSN) ; Shahriarpanah, S ; Asadzadehzanjani, N ; Khaleghpanah, S ; Heidari, S ; Sharif University of Technology
Wiley-VCH Verlag
2016
Abstract
The formation of biomimetic bone-like apatite layers throughout the biopolymer-based hydrogel scaffold is an attractive approach in bone tissue engineering. Here, the starch scaffold was prepared using a combination of particulate leaching and freeze-drying techniques. The fabricated structures were then modified by citric acid to investigate the formation of bone-like apatite layer on the porous citrate-based scaffold after soaking in simulated body fluid (SBF). The Fourier Transform Infrared (FTIR) spectra and X-ray diffraction (XRD) patterns revealed that the B-type carbonated apatite has successfully deposited on the scaffold after immersing in SBF for 28 days. Indeed, high chemical...