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Corrosion resistance and photocatalytic activity evaluation of electrophoretically deposited TiO 2 -rGO nanocomposite on 316L stainless steel substrate
, Article Ceramics International ; Volume 45, Issue 11 , 2019 , Pages 13747-13760 ; 02728842 (ISSN) ; Parvizy, S ; Afshar, A ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
TiO 2 -rGO nanocomposite coatings were obtained by electrophoretic deposition (EPD) technique of TiO 2 nanoparticles and graphene oxide (GO) on stainless steel substrate. First, GO particles were synthesized using a modified Hummers' method. GO was reduced electrochemically to form a coating in the presence of nano-sized TiO 2 particles. The influences of different parameters such as GO concentration, coupling co-electro-deposition parameters (electrophoretic duration and voltage) on thickness, surface morphology and, corrosion behavior of the as-synthesized TiO 2 -rGO nanocomposite coatings were systematically surveyed. The morphology and microstructure were investigated by field emission...
Graphene oxide-starch-based micro-solid phase extraction of antibiotic residues from milk samples
, Article Journal of Chromatography A ; Volume 1591 , 2019 , Pages 7-14 ; 00219673 (ISSN) ; Behkami, S ; Raoofi, M ; Bagheri, H ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In this study, a method was described for the extraction of three antibiotic residues from cow milk samples using a graphene oxide–starch–based nanocomposite. The prepared nanocomposites were employed as an extractive phase for micro-solid phase extraction of antibiotics from cow milk samples. The extracted antibiotics, i.e. amoxicillin, ampicillin and cloxacillin, were subsequently analyzed by high-performance liquid chromatography–ultraviolet detection (HPLC–UV). Important variables associated with the extraction and desorption efficiency were optimized. High extraction efficiencies for the selected antibiotics were conveniently achieved using the starch–based nanocomposite as the...
Injectable chitosan/κ-carrageenan hydrogel designed with au nanoparticles: A conductive scaffold for tissue engineering demands
, Article International Journal of Biological Macromolecules ; Volume 126 , 2019 , Pages 310-317 ; 01418130 (ISSN) ; Doroudian, M ; Ahadpour, A ; Azari, S ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Scaffolds for tissue engineering of specific sites such as cardiac, nerve, and bone tissues need a comprehensive design of three dimensional materials that covers all aspects of chemical composition and physical structures, required for regeneration of desired cells. Hydrogels, possessing highly hydrated and interconnected structures, are promising materials for tissue engineering applications. Improvement of an injectable hydrogel from biocompatible polysaccharides and poly‑N‑isopropyl acryl amide enriched with Au nanoparticles are the main goal of this study. Two main enhancements in this study are included mixture design of the components and addition of Au nanoparticles to access a...
Fabrication, modeling and optimization of lyophilized advanced platelet rich fibrin in combination with collagen-chitosan as a guided bone regeneration membrane
, Article International Journal of Biological Macromolecules ; Volume 125 , 2019 , Pages 383-391 ; 01418130 (ISSN) ; Mashayekhan, S ; Saadatmand, M ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In this study, lyophilized advanced platelet rich fibrin (A-PRF) was used in combination with collagen-chitosan membrane for the first time to combine advantages of both collagen and A-PRF membranes. Response surface methodology (RSM) was used to design the experimental condition and to correlate the effects of parameters, including chitosan/collagen (chit/col) weight ratio and A-PRF concentration on Young's modulus, mesenchymal stem cell (MSCs) viability and degradation rate of the membranes. Results showed that Young's modulus of the membranes was intensified by increasing chit/col weight ratio and decreasing A-PRF concentration from 3 to 8 MPa. Cell viability of MSCs was improved by both...
Activated carbon/metal-organic framework nanocomposite: Preparation and photocatalytic dye degradation mathematical modeling from wastewater by least squares support vector machine
, Article Journal of Environmental Management ; Volume 233 , 2019 , Pages 660-672 ; 03014797 (ISSN) ; Abdi, J ; Taghizadeh, M ; Taghizadeh, A ; Hayati, B ; Shekarchi, A. A ; Vossoughi, M ; Sharif University of Technology
Academic Press
2019
Abstract
Herein, Kiwi peel activated carbon (AC), Materials Institute Lavoisier (MIL-88B (Fe), and AC/MIL-88B (Fe) composite were synthesized and used as catalysts to degrade Reactive Red 198. The material properties were analyzed by the FTIR, BET-BJH, XRD, FESEM, EDX, TGA, and UV–Vis/DRS. The BET surface area of AC, MIL-88B (Fe) and AC/MIL-88B (Fe) was 1113.3, 150.7, and 199.4 m2/g, respectively. The band gap values (Eg) estimated by Tauc plot method, were obtained 5.06, 4.19 and 3.79 eV for AC, MIL-88B (Fe) and AC/MIL-88B (Fe), respectively. The results indicated that the AC/MIL-88B (Fe) composite had higher photocatalytic activity (99%) than that of pure AC (79%) and MIL-88B (Fe) catalysts (87%)....
Nanorod carbon nitride as a carbo catalyst for selective oxidation of hydrogen sulfide to sulfur
, Article Journal of Hazardous Materials ; Volume 364 , 2019 , Pages 218-226 ; 03043894 (ISSN) ; Eskandari, M. M ; Rashidi, A ; Baghalha, M ; Hassanisadi, M ; Hamzehlouyan, T ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Two-dimensional mesoporous carbon nitride and its highly efficient nanorod framework were prepared via hard-templating method. The obtained materials were fully characterized. The results showed that the samples structural ordering and morphology were similar to those of the parent silica templates; they had large pore volumes as well as high surface area structures. Carbon nitride carbocatalysts were used for H2S selective oxidation. The catalytic tests were carried out at 190, 210 and 230 °C in a fixed bed reactor. The obtained selectivity values for mesoporous carbon nitride rod and mesoporous carbon nitride toward elemental sulfur at 190 °C were 88.8% and 83%, respectively. Both samples...
Diastereoselective construction of a functionalized dihydro-pyridazine-based spirooxindole scaffold: Via C-3 umpolung of isatin N, N ′-cyclic azomethine imine
, Article New Journal of Chemistry ; Volume 43, Issue 26 , 2019 , Pages 10318-10323 ; 11440546 (ISSN) ; Eslami, M ; Siahpoosh, A ; Hoda, G ; Sharif University of Technology
Royal Society of Chemistry
2019
Abstract
Herein, functionalized spiro[indoline-3,5′-pyrazolo[1,2-a]pyridazine]-7′-carbonitrile containing two contiguous chiral stereocenters was efficiently synthesized in a satisfactory yield (up to 91% yield) and with excellent diastereoselectivity. We have reached this satisfactory yield by DABCO-catalyzed [3+3] annulation reactions of an isatin N,N′-cyclic azomethine imine 1,3-dipole with a Knoevenagel intermediate in dichloromethane (DCM) as solvent at ambient temperature; this was an entirely new strategy for creating one quaternary stereogenic center at the position-3 of an oxindole structure using an abnormal tandem Michael addition, N-cyclization, and a unique approach via the azomethine...
Diastereoselective construction of a functionalized dihydro-pyridazine-based spirooxindole scaffold: via C-3 umpolung of isatin N, N ′-cyclic azomethine imine
, Article New Journal of Chemistry ; Volume 43, Issue 26 , 2019 , Pages 10318-10323 ; 11440546 (ISSN) ; Eslami, M ; Siahpoosh, A ; Hoda, G ; Sharif University of Technology
Royal Society of Chemistry
2019
Abstract
Herein, functionalized spiro[indoline-3,5′-pyrazolo[1,2-a]pyridazine]-7′-carbonitrile containing two contiguous chiral stereocenters was efficiently synthesized in a satisfactory yield (up to 91% yield) and with excellent diastereoselectivity. We have reached this satisfactory yield by DABCO-catalyzed [3+3] annulation reactions of an isatin N,N′-cyclic azomethine imine 1,3-dipole with a Knoevenagel intermediate in dichloromethane (DCM) as solvent at ambient temperature; this was an entirely new strategy for creating one quaternary stereogenic center at the position-3 of an oxindole structure using an abnormal tandem Michael addition, N-cyclization, and a unique approach via the azomethine...
In vitro study: bond strength, electrochemical and biocompatibility evaluations of TiO2/Al2O3 reinforced hydroxyapatite sol–gel coatings on 316L SS
, Article Surface and Coatings Technology ; 2020 ; Afshar, A ; Sharif University of Technology
Elsevier B.V
2020
Abstract
To improve the biocompatibility and corrosion resistance of 316L SS (Stainless Steel) metal implants, HAp(hydroxyapatite)/TiO2/Al2O3 nanocomposite coating was created using dip sol-gel method sintered at 550 °C. The weight percentage of TiO2+ Al2O3 in these coatings was 20, 30, and 40% wt. In this study, characterization was performed using FTIR (Fourier-Transform Infrared Spectroscopy), XRD, FE-SEM (Field Emission Scanning Electron Microscope), EDS (Energy Dispersive Spectroscopy), DLS (Dynamic Light Scattering), Pull-off, and AFM (Atomic Force Microscopy) analysis. The potentiodynamic polarization and EIS (Electrochemical Impedance Spectroscopy) were performed in the simulated body fluid...
In situ two-step preparation of 3D NiCo-BTC MOFs on a glassy carbon electrode and a graphitic screen printed electrode as nonenzymatic glucose-sensing platforms
, Article ACS Sustainable Chemistry and Engineering ; Volume 8, Issue 38 , 2020 , Pages 14340-14352 ; Shahrokhian, S ; Hosseini, H ; Sharif University of Technology
American Chemical Society
2020
Abstract
In the present study, a rational two-step strategy is employed for the green, fast, very simple, and highly controllable synthesis of the bimetallic nickel-cobalt-based metal-organic frameworks (MOFs) on glassy carbon substrates by in situ transformation of nickel-cobalt-layered double hydroxide nanosheet (NiCo-LDHs NSs) intermediates into nickel-cobalt-benzene tricarboxylic acid MOFs (E-NiCo-BTC MOFs). The structural characteristics of the electrode materials in each step were investigated via Fourier transform infrared spectroscopy, X-ray diffraction, energy dispersive X-ray spectroscopy, elemental mapping, field emission scanning electron microscopy, and transmittance electron microscopy....
Introducing an affordable catalyst for biohydrogen production in microbial electrolysis cells
, Article Journal of Bioscience and Bioengineering ; Volume 129, Issue 1 , 2020 , Pages 67-76 ; Yaghmaei, S ; Abdi, K ; Mardanpour, M. M ; Haddadi, S. A ; Sharif University of Technology
Elsevier B.V
2020
Abstract
This study reports the fabrication of a new cathode electrode assembly using polyaniline (PANI) and graphene on a stainless steel mesh (SSM) as an alternative for the conventional expensive cathode of microbial electrolysis cells (MECs). With respect to the previous efforts to propose an efficient and cost-effective alternative for platinum (Pt) catalysts and cathode electrodes, the present study investigates the assessment of different catalysts to elucidate the potential of the modified SSM cathode electrode for larger-scale MECs. In the case of feeding dairy wastewater to the MEC, the maximum hydrogen production rate and COD removal were obtained by SSM/PANI/graphene cathode and had the...
High-gravity-assisted green synthesis of palladium nanoparticles: the flowering of nanomedicine
, Article Nanomedicine: Nanotechnology, Biology, and Medicine ; Volume 30 , November , 2020 ; Rabiee, N ; Bagherzadeh, M ; Ghadiri, A. M ; Fatahi, Y ; Dinarvand, R ; Webster, T. J ; Sharif University of Technology
Elsevier Inc
2020
Abstract
This study investigated the synthesis of Pd nanoparticles (NPs) using a high-gravity technique mediated by Salvia hispanica leaf extracts. Biological assays confirmed their antibacterial activity against gram positive (S. aureus) and gram negative (E. coli) bacteria with significant antioxidant activity in comparison with the standards as well as low cellular toxicity on PC12 and HEK293 cell lines. To the best of our knowledge, this study can be considered as the first investigation of Pd-NPs synthesized by Salvia hispanica leaf extracts assisted by a high-gravity technique. In addition, the mentioned green synthesis procedure led to the formation of nanoparticles with considerable...
Ag-doped magnetic metal organic framework as a novel nanostructured material for highly efficient antibacterial activity
, Article Environmental Research ; Volume 188 , 2020 ; Abdi, J ; Vossoughi, M ; Alemzadeh, I ; Sharif University of Technology
Academic Press Inc
2020
Abstract
In the last decades, numerous attempts have been made to prevent microbial pollution spreading, using antibacterial agents. Zeolitic imidazolate framework-8 (ZIF-8) belongs to a subgroup of metal organic frameworks (MOFs) merits of attention due to the zinc ion clusters and its effective antibacterial activity. In this work, Ag-doped magnetic microporous γ-Fe2O3@SiO2@ZIF-8-Ag (FSZ-Ag) was successfully synthesized by a facile methodology in room temperature and used as an antibacterial agent against the growth of the Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus bacteria. Several characterization methods were applied to analyze the properties of the materials, and the...
Folate conjugated hyaluronic acid coated alginate nanogels encapsulated oxaliplatin enhance antitumor and apoptosis efficacy on colorectal cancer cells (HT29 cell line)
, Article Toxicology in Vitro ; Volume 65 , 2020 ; Zare Karizi, S ; Safaie Javan, R ; Mirzaie, A ; Noorbazargan, H ; Akbarzadeh, I ; Rezaie, H ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Oxaliplatin (OXA) has been widely used for treatment of colorectal cancer. In this study, to enhance antitumor and apoptosis efficacy, OXA was encapsulated in a novel folate conjugated hyaluronic acid coated alginate nanogels (F/HA/AL/OXA). The F/HA/AL/OXA nanogels were prepared by cross-linking process. The physico-chemical properties of F/HA/AL/OXA nanogels were characterized using scanning electron microscopy, transmission electron microscopy, fourier transform infrared spectroscopy, dynamic light scattering, and fluorescent spectrophotometry. The in-vitro antitumor activity of free OXA, AL, HA/AL, HA/AL/OXA and F/HA/AL/OXA nanogels were assessed using MTT assay against colorectal cancer...
Fabrication of a sensitive and fast response electrochemical glucose sensing platform based on co-based metal-organic frameworks obtained from rapid in situ conversion of electrodeposited cobalt hydroxide intermediates
, Article Talanta ; Volume 210 , 2020 ; Ezzati, M ; Hosseini, H ; Sharif University of Technology
Elsevier B.V
2020
Abstract
In this study, for the first time, we reported a fast and facile three-step in situ strategy for direct controllable growth of the Co3(BTC)2 MOFs thin films on the GCE, through the rapid conversion of the electrodeposited Co(OH)2 nano-flakes on rGO/GCE, to crystalline rectangular bar-shape structures of MOFs. X-ray diffraction spectroscopy, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, energy dispersive X-ray spectroscopy and elemental mapping analysis used to the structural and morphological characterization of the well-synthesized MOFs. The as-prepared Co3(BTC)2 MOFs were used to construct a non-enzymatic sensing platform for determining the glucose...
Copper(ii) ions supported on functionalized graphene oxide: an organometallic nanocatalyst for oxidative amination of azolesviaC-H/C-N bond activation
, Article New Journal of Chemistry ; Volume 45, Issue 6 , 2021 , Pages 3242-3251 ; 11440546 (ISSN) ; Mahmoodi Hashemi, M ; Roknizadeh, M ; Nasiri, S ; Ramazani Saadatabadi, A ; Sharif University of Technology
Royal Society of Chemistry
2021
Abstract
Graphene oxide (GO) was chemically modified withpara-aminobenzoic acid (PABA) to immobilize copper(ii) ions on its surface and used as a nanocatalyst for the oxidative C(sp2)-H bond amination reaction. A practical method to prepare Cu2+supported onpara-aminobenzoic acid grafted on GO was reported. The prepared Cu2+@GO/PABA was characterized by FT-IR, XRD, SEM, AFM, TEM, UV-Vis, and ICP techniques. The results showed that the morphology, distribution, and loading of copper ions could be well-adjusted by grafting of PABA on GO. Moreover, just 2 mol% of Cu2+@GO-PABA could catalyze the C-H activation reaction of benzoxazole and benzothiazole with secondary amines in >94% yields. Also, the...
Improved green biosynthesis of chitosan decorated Ag- and Co3O4-nanoparticles: A relationship between surface morphology, photocatalytic and biomedical applications
, Article Nanomedicine: Nanotechnology, Biology, and Medicine ; Volume 32 , 2021 ; 15499634 (ISSN) ; Rabiee, N ; Bagherzadeh, M ; Ghadiri, A.M ; Fatahi, Y ; Dinarvand, R ; Webster, T. J ; Sharif University of Technology
Elsevier Inc
2021
Abstract
AgNPs@Chitosan and Co3O4-NPs@Chitosan were fabricated with Salvia hispanica. Results showed MZI values of 5 and 30 mm for Co3O4-NPs- and AgNPs@Chitosan against S. aureus, and 15 and 21 mm for Co3O4-NPs- and AgNPs@Chitosan against E. coli (24 h, 20 μg/mL), respectively. MTT assays showed up to 80% and 90%, 71% and 75%, and 91% and 94% mammalian cell viability for the green synthesized, chemically synthesized AgNPs and green synthesized AgNPs@Chitosan for HEK-293 and PC12 cells, respectively, and 70% and 71%, 59% and 62%, and 88% and 73% for the related Co3O4-NPs (24 h, 20 μg/mL). The photocatalytic activities showed dye degradation after 135 and 105 min for AgNPs@Chitosan and...
Preparation and characterization of self-electrical stimuli conductive gellan based nano scaffold for nerve regeneration containing chopped short spun nanofibers of PVDF/MCM41 and polyaniline/graphene nanoparticles: Physical, mechanical and morphological studies
, Article International Journal of Biological Macromolecules ; Volume 167 , 2021 , Pages 881-893 ; 01418130 (ISSN) ; S. A., A. R ; H Shirazi, F ; Nemati, N. H ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Conductive self -electrical stimuli bioactive scaffolds could be used the potential for peripheral nerve regeneration with the maximum efficiency. To produce such conductive self-electrical stimuli bioactive scaffolds, chopped spun piezoelectric nanofibers of polyvinylidene fluoride/mesoporous silica nanoparticle (PVDF/MCM41) are prepared and incorporated in gellan/polyaniline/graphene (gellan/PAG) nanocomposites which have been previously prepared by incorporation of polyaniline/graphene (PAG) nanoparticles in gellan gel at 80 °C. Highly conductive binary doped polyaniline/graphene nanoparticles are prepared by chemical oxidative polymerization of aniline monomer using in-suite...
Fabrication and characterization of an injectable reinforced composite scaffold for cartilage tissue engineering: An in vitro study
, Article Biomedical Materials (Bristol) ; Volume 16, Issue 4 , 2021 ; 17486041 (ISSN) ; Mashayekhan, S ; Zarei, F ; Sayyahpour, F. A ; Taghiyar, L ; Eslaminejad, M. B ; Sharif University of Technology
IOP Publishing Ltd
2021
Abstract
There are limitations in current medications of articular cartilage injuries. Although injectable bioactive hydrogels are promising options, they have decreased biomechanical performance. Researchers should consider many factors when providing solutions to overcome these challenges. In this study, we created an injectable composite hydrogel from chitosan and human acellular cartilage extracellular matrix (ECM) particles. In order to enhance its mechanical properties, we reinforced this hydrogel with microporous microspheres composed of the same materials as the structural building blocks of the scaffold. Articular cartilage from human donors was decellularized by a combination of physical,...
Mesoporous nanostructures of NiCo-LDH/ZnCo2O4 as an efficient electrocatalyst for oxygen evolution reaction
, Article Journal of Colloid and Interface Science ; Volume 604 , 2021 , Pages 832-843 ; 00219797 (ISSN) ; Shahrokhian, S ; Amini, M. K ; Sharif University of Technology
Academic Press Inc
2021
Abstract
Increasing energy demands for pollution-free and renewable energy technologies have stimulated intense research on the development of inexpensive, highly efficient, and stable non-noble metal electrocatalysts for oxygen evolution reaction (OER). In this study, a superior OER performance was achieved using a tri-metallic (Zn, Co, Ni) high-performance electrocatalyst. We successfully fabricated a peony-flower-like hierarchical ZnCo2O4 through an additive-free hydrothermal reaction followed by heat treatment. Then NiCo-LDH (layered double hydroxides) nano-flakes was electrodeposited on the ZnCo2O4/GCE surface to prepare NiCo-LDH/ZnCo2O4/GCE which was used as electrode for OER. The structure and...