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    Magnetite nanoparticle as a support for stabilization of chondroitinase ABCI

    , Article Artificial Cells, Nanomedicine and Biotechnology ; Volume 47, Issue 1 , 2019 , Pages 2721-2728 ; 21691401 (ISSN) Askaripour, H ; Vossoughi, M ; Khajeh, K ; Alemzadeh, I ; Sharif University of Technology
    Taylor and Francis Ltd  2019
    Chondroitinase ABCI (cABCI) is a drug enzyme that can be used to treat spinal cord injuries. Due to low thermal stability of cABCI, this enzyme was immobilized on Fe3O4 nanoparticle to increase its thermal stability. The size and morphology, structure and magnetic property of the Fe3O4 nanoparticles were characterized by the analyses of SEM, XRD and VSM, respectively, and FTIR spectroscopy was employed to confirm the immobilization of cABCI on the surface of Fe3O4 nanoparticles. The results indicated that the optimum conditions for pH, temperature, cABCI-to-Fe3O4 mass ratio and incubation time in immobilization process were 6.5, 15 °C, 0.75 and 4.5 h, respectively, and about 0.037 mg cABCI... 

    Antibacterial properties of nanoporous graphene oxide/cobalt metal organic framework

    , Article Materials Science and Engineering C ; Volume 104 , 2019 ; 09284931 (ISSN) Hatamie, S ; Ahadian, M. M ; Soufi Zomorod, M ; Torabi, S ; Babaie, A ; Hosseinzadeh, S ; Soleimani, M ; Hatami, N ; Wei, Z. H ; Sharif University of Technology
    Elsevier Ltd  2019
    Metal-organic framework (MOF) based graphene oxide (GO) recently merits of attention because of the relative correspondence of GO with metal ions and organic binding linkers. Furthermore, introducing the GO to the Co-MOF to make a new nanoporous hybrid have are improved the selectivity and stability of the Co-MOF. Here the graphene oxide/cobalt metal organic framework (GO/Co-MOF) was synthesized by a solvothermal process using cobalt salt and terephthalic acid and used for biocidal activity, against the growth of the Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus bacteria. X-ray diffraction, Fourier transform infrared spectroscopy and Raman spectroscopy were confirmed... 

    Short-term associations between daily mortality and ambient particulate matter, nitrogen dioxide, and the air quality index in a Middle Eastern megacity

    , Article Environmental Pollution ; Volume 254 , 2019 ; 02697491 (ISSN) Amini, H ; Trang Nhung, N. T ; Schindler, C ; Yunesian, M ; Hosseini, V ; Shamsipour, M ; Hassanvand, M. S ; Mohammadi, Y ; Farzadfar, F ; Vicedo Cabrera, A. M ; Schwartz, J ; Henderson, S. B ; Künzli, N ; Sharif University of Technology
    Elsevier Ltd  2019
    There is limited evidence for short-term association between mortality and ambient air pollution in the Middle East and no study has evaluated exposure windows of about a month prior to death. We investigated all-cause non-accidental daily mortality and its association with fine particulate matter (PM2.5), nitrogen dioxide (NO2), and the Air Quality Index (AQI) from March 2011 through March 2014 in the megacity of Tehran, Iran. Generalized additive quasi-Poisson models were used within a distributed lag linear modeling framework to estimate the cumulative effects of PM2.5, NO2, and the AQI up to a lag of 45 days. We further conducted multi-pollutant models and also stratified the analyses by... 

    Gas chromatographic fingerprint analysis of secondary metabolites of Stachys lanata (Stachys byzantine C. Koch) combined with antioxidant activity modelling using multivariate chemometric methods

    , Article Journal of Chromatography A ; Volume 1602 , 2019 , Pages 432-440 ; 00219673 (ISSN) Aminfar, P ; Abtahi, M ; Parastar, H ; Sharif University of Technology
    Elsevier B.V  2019
    S. lanata has been traditionally used as a medicinal plant due to its various biological activities such as antioxidant activity. Therefore, identification and quality control studies of this plant are of great importance. To this end, gas chromatography (GC) combined with chemometrics was proposed for fingerprint analysis of S. lanata samples. This study sought to classify GC fingerprints of twenty-eight S. lanata samples from eight different regions of Iran and more importantly, to correlate fingerprints to the antioxidant activity to select S. lanata volatile antioxidant markers. S. lanata samples were classified into five and three classes using partial least squares-discriminant... 

    Inorganic nanomaterials for chemo/photothermal therapy: a promising horizon on effective cancer treatment

    , Article Biophysical Reviews ; Volume 11, Issue 3 , 2019 , Pages 335-352 ; 18672450 (ISSN) Khafaji, M ; Zamani, M ; Golizadeh, M ; Bavi, O ; Sharif University of Technology
    Springer Verlag  2019
    During the last few decades, nanotechnology has established many essential applications in the biomedical field and in particular for cancer therapy. Not only can nanodelivery systems address the shortcomings of conventional chemotherapy such as limited stability, non-specific biodistribution and targeting, poor water solubility, low therapeutic indices, and severe toxic side effects, but some of them can also provide simultaneous combination of therapies and diagnostics. Among the various therapies, the combination of chemo- and photothermal therapy (CT-PTT) has demonstrated synergistic therapeutic efficacies with minimal side effects in several preclinical studies. In this regard,... 

    Synthesis and characterization of magnetic hybrid nanomaterials via RAFT polymerization: A pH sensitive drug delivery system

    , Article Colloids and Surfaces B: Biointerfaces ; Volume 174 , 2019 , Pages 153-160 ; 09277765 (ISSN) Pourjavadi, A ; Kohestanian, M ; Shirzad, M ; Sharif University of Technology
    Elsevier B.V  2019
    Herein, a facile and versatile method for the synthesis of a novel magnetic nanocarrier via surface- initiated reversible addition-fragmentation chain transfer (RAFT) polymerization is introduced. At first, RAFT agent was successfully attached to the surface of Fe 3 O 4 nanoparticles and, then, poly (glycidyl methacrylate) (PGMA) chains were grown and anchored onto the surface of Fe 3 O 4 nanoparticles. At the end, hydrazine (Hy) groups were introduced to the PGMA chains via reaction between epoxy rings and hydrazine molecules. Doxorubicin (DOX) was covalently conjugated to the prepared nanocarrier (Fe 3 O 4 @PGMA@Hy) through a hydrazone linkage. The in vitro drug release of Fe 3 O 4... 

    Light olefin production on the Co-Ni catalyst: Calcination conditions, and modeling and optimization of the process conditions by a statistical method

    , Article New Journal of Chemistry ; Volume 44, Issue 18 , 2020 , Pages 7467-7483 Arsalanfar, M ; Akbari, M ; Mirzaei, N ; Abdouss, M ; Sharif University of Technology
    Royal Society of Chemistry  2020
    The present work is comprised of two main parts. In part 1 the Co-Ni/γ-Al2O3 catalyst was prepared using a sol-gel procedure. Then the effect of calcination variables including the calcination temperature and time on the catalytic performance for production of light olefins was investigated and optimized. The obtained results have shown that the catalyst which was calcined at 550 °C for 6 h has revealed the better catalytic performance for production of light olefins. In part 2 the effect of process conditions including the reaction temperature, H2/CO feed ratio and total reaction pressure on the catalytic performance (CO conversion%, (C2-C4) selectivity% and C5+ selectivity%) was... 

    3D Bioprinting of oxygenated cell-laden gelatin methacryloyl constructs

    , Article Advanced Healthcare Materials ; Volume 9, Issue 15 , 2020 Erdem, A ; Darabi, M. A ; Nasiri, R ; Sangabathuni, S ; Ertas, Y. N ; Alem, H ; Hosseini, V ; Shamloo, A ; Nasr, A. S ; Ahadian, S ; Dokmeci, M. R ; Khademhosseini, A ; Ashammakhi, N ; Sharif University of Technology
    Wiley-VCH Verlag  2020
    Cell survival during the early stages of transplantation and before new blood vessels formation is a major challenge in translational applications of 3D bioprinted tissues. Supplementing oxygen (O2) to transplanted cells via an O2 generating source such as calcium peroxide (CPO) is an attractive approach to ensure cell viability. Calcium peroxide also produces calcium hydroxide that reduces the viscosity of bioinks, which is a limiting factor for bioprinting. Therefore, adapting this solution into 3D bioprinting is of significant importance. In this study, a gelatin methacryloyl (GelMA) bioink that is optimized in terms of pH and viscosity is developed. The improved rheological properties... 

    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 Ezzati, M ; Shahrokhian, S ; Hosseini, H ; Sharif University of Technology
    American Chemical Society  2020
    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.... 

    Synthesis of a novel magnetic starch-alginic acid-based biomaterial for drug delivery

    , Article Carbohydrate Research ; Volume 487 , 2020 Forouzandehdel, S ; Forouzandehdel, S ; Rezghi Rami, M ; Sharif University of Technology
    Elsevier Ltd  2020
    The magnetic composite hydrogel was fabricated by the graft copolymerization of itaconic acid (IA) onto starch and Alginic acid in the presence graphene sheets (Gr) and Fe3O4 nanoparticles (Fe3O4@Gr-IA/St-Alg) for Guaifenesin (GFN) delivery and wound healing. The Fe3O4@Gr-IA/St-Alg biomaterial is a hydrogel network endowed the material with magnetic property. In addition, GFN not only achieved effectively bound to the magnetic hydrogel, but also released in a controlled manner. The using external magnetic field has significantly positive influence on the drug release rate. To close, these hydrogel drug carriers offer a favorable platform for magnetically targeted drug delivery as well as a... 

    Graphene oxide negatively regulates cell cycle in embryonic fibroblast cells

    , Article International Journal of Nanomedicine ; Volume 15 , 2020 , Pages 6201-6209 Hashemi, E ; Akhavan, O ; Shamsara, M ; Ansari Majd, S ; Sanati, M. H ; Daliri Joupari, M ; Farmany, A ; Sharif University of Technology
    Dove Medical Press Ltd  2020
    Background: Unique properties of graphene and its derivatives make them attractive in the field of nanomedicine. However, the mass application of graphene might lead to side effects, which has not been properly addressed in previous studies, especially with regard to its effect on the cell cycle. Methods: The effect of two concentrations (100 and 200 μg/mL) of nano-and microsized graphene oxide (nGO and mGO) on apoptosis, cell cycle, and ROS generation was studied. The effect of both sizes on viability and genotoxicity of the embryonic fibroblast cell cycle was evaluated. MTT and flow cytometry were applied to evaluate the effects of graphene oxide (GO) nanosheets on viability of cells.... 

    Burgeoning polymer nano blends for improved controlled drug release: A review

    , Article International Journal of Nanomedicine ; Volume 15 , March , 2020 , Pages 4363-4392 Maghsoudi, S ; Shahraki, B. T ; Rabiee, N ; Fatahi, Y ; Dinarvand, R ; Tavakolizadeh, M ; Ahmadi, S ; Rabiee, M ; Bagherzadeh, M ; Pourjavadi, A ; Farhadnejad, H ; Tahriri, M ; Webster, T. J ; Tayebi, L ; Sharif University of Technology
    Dove Medical Press Ltd  2020
    With continual rapid developments in the biomedical field and understanding of the important mechanisms and pharmacokinetics of biological molecules, controlled drug delivery systems (CDDSs) have been at the forefront over conventional drug delivery systems. Over the past several years, scientists have placed boundless energy and time into exploiting a wide variety of excipients, particularly diverse polymers, both natural and synthetic. More recently, the development of nano polymer blends has achieved noteworthy attention due to their amazing properties, such as biocompatibility, biodegradability and more importantly, their pivotal role in controlled and sustained drug release in vitro and... 

    pH and thermal dual-responsive poly(NIPAM-co-GMA)-coated magnetic nanoparticles via surface-initiated RAFT polymerization for controlled drug delivery

    , Article Materials Science and Engineering C ; Volume 108 , 2020 Pourjavadi, A ; Kohestanian, M ; Streb, C ; Sharif University of Technology
    Elsevier Ltd  2020
    Herein, a novel type of multifunctional magnetic nanoparticles with dual thermal and pH-responsive behavior was fabricated as the carrier for delivery of doxorubicin (DOX). Fe3O4@SiO2 magnetic nanoparticles, were grafted with polymer brushes consisting of poly (NIPAM-co-GMA) (PNG) chains via surface initiated reversible addition-fragmentation chain transfer (SI-RAFT) polymerization. The polymer brushes were then modified with hydrazine groups as DOX binding sites. The prepared multifunctional magnetic nanoparticles were characterized by FT-IR, 1H NMR, XPS, TGA, DLS, VSM, GPC, TEM, and XRD analysis. The in vitro drug release of the multifunctional magnetic nanoparticles was examined at 37 °C... 

    Ag-doped magnetic metal organic framework as a novel nanostructured material for highly efficient antibacterial activity

    , Article Environmental Research ; Volume 188 , 2020 Rahmati, Z ; Abdi, J ; Vossoughi, M ; Alemzadeh, I ; Sharif University of Technology
    Academic Press Inc  2020
    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... 

    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 Shahrokhian, S ; Ezzati, M ; Hosseini, H ; Sharif University of Technology
    Elsevier B.V  2020
    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... 

    Degradation of phenanthrene and anthracene by Nocardia otitidiscaviarum strain TSH1, a moderately thermophilic bacterium

    , Article Journal of Applied Microbiology ; Volume 105, Issue 2 , 11 July , 2008 , Pages 398-406 ; 13645072 (ISSN) Zeinali, M ; Vossoughi, M ; Ardestani, S. K ; Sharif University of Technology
    Aims: The metabolism of phenanthrene and anthracene by a moderate thermophilic Nocardia otitidiscaviarum strain TSH1 was examined. Methods and Results: When strain TSH1 was grown in the presence of anthracene, four metabolites were identified as 1,2-dihydroxy-1,2-dihydroanthracene, 3-(2-carboxyvinyl)naphthalene-2-carboxylic acid, 2,3-dihydroxynaphthalene and benzoic acid using gas chromatography-mass spectrometry (GC-MS), reverse phase-high performance liquid chromatography (RP-HPLC) and thin-layer chromatography (TLC). Degradation studies with phenanthrene revealed 2,2′-diphenic acid, phthalic acid, 4-hydroxyphenylacetic acid, o-hydroxyphenylacetic acid, benzoic acid, a phenanthrene... 

    Low temperature self-agglomeration of metallic Ag nanoparticles on silica sol-gel thin films

    , Article Journal of Physics D: Applied Physics ; Volume 41, Issue 19 , 2008 ; 00223727 (ISSN) Akhavan, O ; Azimirad, R ; Moshfegh, A. Z ; Sharif University of Technology
    A facile sol-gel synthesis for self-agglomeration of metallic silver nanoparticles, with fcc crystalline structure, on the silica surface in a low annealing temperature has been introduced. X-ray photoelectron spectroscopy (XPS) revealed initial agglomeration (∼30 times greater than the nominal concentration of Ag) of the nanoparticles on the surface of the dried film (100 °C) and also their oxidation as well as easy diffusion (with 0.08 eV required activation energy) into the porous silica thin films, by increasing the annealing temperature (200-400 °C). By raising the Ag concentration from 0.2 to 1.6 mol% in the sol, the average size of the Ag nanoparticles increased from ∼5 to 37 nm... 

    Two-dimensional quantum simulation of scaling effects in ultrathin body MOSFET structure: NEGF approach

    , Article 14th International Workshop on the Physics of Semiconductor Devices, IWPSD, Mumbai, 16 December 2007 through 20 December 2007 ; 2007 , Pages 240-242 ; 9781424417285 (ISBN) Orouji, A.A ; Dehdashti, N ; Faez, R ; Sharif University of Technology
    For the first time, we present self-consistent solution of ultrathin body device structures to investigate the device parameters variation on the characteristics of nanoscale MOSFET. Our two dimensional (2-D) device simulator Is based on Nonequlibrium Green's Function (NEGF) forma lism. Starting from a basic structure (DG-MOSFET) with a gate length of 10 nm, variation of gate length, channel thickness, gate oxide parameters was carried out in connection with the numerical calculation of device characteristics. In this work Quantum transport equations are solved in 2-D by NEGF method in active area of the device to obtain the charge density and Poisson's equation is solved in entire domain of... 

    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) Kiani, M ; Rabiee, N ; Bagherzadeh, M ; Ghadiri, A.M ; Fatahi, Y ; Dinarvand, R ; Webster, T. J ; Sharif University of Technology
    Elsevier Inc  2021
    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 of amine–modified lignin and its applicability toward online micro–solid phase extraction of valsartan and losartan in urine samples

    , Article Journal of Chromatography A ; Volume 1643 , 2021 ; 00219673 (ISSN) Taherzadeh Ghahfarrokhi, M ; Zeinali, S ; Bagheri, H ; Sharif University of Technology
    Elsevier B.V  2021
    In the present work, with the focus on an environmentally–friendly approach, some gels were prepared by synthesizing amine–modified lignin, extracted from sugarcane bagasse, and further esterification and subsequent freeze–drying. These lignin–based gels were implemented as extractive phases in an online micro–solid phase extraction (μSPE) setup in conjunction with high performance liquid chromatography (HPLC) with UV detector. The developed method was used for analytical determination of valsartan and losartan in urine samples. To study the effect of the functionalization process, the efficiency of the unmodified lignin and the functionalized lignin were compared both in the absence and the...