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    Fabrication of multifunctional microfibrous and nanofibrous cellulose carriers and comparison of cell adhesion and spreading potential on them

    , Article Biointerface Research in Applied Chemistry ; Volume 10, Issue 3 , 2020 , Pages 5387-5391 Ramezan Kalmer, R ; Mohammadi, M ; Najafpour, G ; Golizadeh, M ; Haghighatnia, Y ; Karimi, A ; Sharif University of Technology
    AMG Transcend Association  2020
    Fibrous biomaterials have received much attention in tissue engineering and regenerative medicine due to their morphology, resembling extracellular matrix. In comparison to synthetic fibers, cellulose based fibers have interesting properties for cellular applications such as biodegradability, biocompatibility, simple preparation and their potential for chemical modification. Among cellulose derivatives, carboxymethyl cellulose and quaternized cellulose are the most important and valuable cellulose ethers which have anionic and cationic surface charge. In this research, we report the fabrication of multifunctional cellulose microfibrous and nanofibrous scaffolds and the comparison of adhesion... 

    A comparative studyof cellulose agricultural wastes (almond shell, pistachio shell, walnut shell, tea waste and orange peel) for adsorption of violet B dye from aqueous solutions

    , Article Oriental Journal of Chemistry ; Vol. 30, issue. 4 , 2014 , p. 2091-2098 Hashemian, S ; Shayegan, J ; Sharif University of Technology
    Adsorption of violet B azo dye from aqueous solutions was studied by different cellulose agricultural waste materials (almond shell (AS), pistachio shell (PS), walnut shell (WS), Tea waste (TW) and orange peel (OP)). Cellulose agriculturalwaste sorbents characterized by FTIR and SEM methods. The effects of different parameters such as contact time, pH, adsorbent dosage and initial dye concentration were studied. Maximum removal of dye was obtained at contact time of 90 min and pH 11. The adsorption of violet B was fitted by pseudo-second-order kinetic model. The Langmuir isotherm model was better fitted than Freundlichmodel. The results showed that the adsorption efficiency of violet B by... 

    Preparation of mesh-reinforced cellulose acetate forward osmosis membrane with very low surface roughness

    , Article Korean Journal of Chemical Engineering ; Volume 34, Issue 12 , 2017 , Pages 3170-3177 ; 02561115 (ISSN) Mirkhalili, S. M ; Mousavi, S. A ; Ramazani Saadat Abadi, A ; Sadeghi, M ; Sharif University of Technology
    Mesh-reinforced cellulose acetate (CA)-based membranes were prepared for forward osmosis (FO) by immersion precipitation. Casting compositions such as CA percent and 1, 4-dioxane/acetone ratio and also preparation conditions such as evaporation time, coagulation bath and annealing temperatures were tested for membranes’ performance. The results were compared with commercially CTA membranes. The best membrane (17.9% polymer and 1, 4-dioxane/acetone ratio of 1.89) showed water flux of 9.3 L/m2h (LMH) and RSF of 0.536 mol NaCl/m2h. Moreover, the membrane structure was reinforced by a polyester mesh, which created micro pores in the back of the membrane. This caused higher water flux and RSF... 

    In-situ formation and entrapment of Ag/AgCl photocatalyst inside cross-linked carboxymethyl cellulose beads: A novel photoactive hydrogel for visible-light-induced photocatalysis

    , Article Journal of Photochemistry and Photobiology A: Chemistry ; Volume 398 , 2020 Heidarpour, H ; Golizadeh, M ; Padervand, M ; Karimi, A ; Vossoughi, M ; Tavakoli, M. H ; Sharif University of Technology
    Elsevier B.V  2020
    In this work, a novel photoactive cellulose-based hydrogel was prepared by simultaneous AgCl formation and entrapment inside Al (III) and Fe (III) cross-linked carboxymethyl cellulose beads. Physio-chemical and optical properties of the synthesized composites were well characterized by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, elemental mapping, Fourier transform infrared (FTIR) spectroscopy, photoluminescence (PL), and diffuse reflectance spectroscopy (DRS). The photocatalytic activity of hydrogels was evaluated by the degradation of rhodamine B (RhB), as a model environmental pollutant. A comparative study showed that... 

    Modified CMC. 4. Ceric-initiated methacrylonitrile graft polymerization onto carboxymethylcellulose

    , Article Journal of Polymer Materials ; Volume 21, Issue 4s , 2004 , Pages 351-359 ; 09738622 (ISSN) Pourjavadi, A ; Zohuriaan Mehr, M. J ; Pooraghaberar, A ; Hosseinzadeh, H ; Sharif University of Technology
    Graft copolymerization of methacrylonitrile (MAN) onto carboxymethylcellulose (CMC) was carried out under argon atmosphere in a homogeneous aqueous medium by using ceric ammonium nitrate (CAN) as an initiator. The FTIR spectroscopy and solubility characteristics of the products were used for confirming the graft copolymer formation. The effect of the concentration of the initiator, monomer and polysaccharide as well as the reaction time and temperature on the graft copolymerization reactions were investigated to achieve the optimum grafting conditions (i.e. CAN 0.00065 mol/L, MAN 0.85 mol/L, CMC 1% W/V, reaction temperature 45°C, and reaction time 2 h). According to the empirical rates of... 

    Production of Biocellulose Nanofibers by Gluconacetobacter and Evaluation of the Release of the Azithromycin Antibiotic Loaded on It in a Simulated Gastric Fluid

    , M.Sc. Thesis Sharif University of Technology Gholizadeh, Yousef (Author) ; Alemzadeh, Iran (Supervisor)
    Bacterial cellulose is a kind of cellulose with high purity and Crystallization, which is mainly produced by gram-negative bacteria in aqueous media containing a sugar source.Cellulose produced by this method is in the form of nanofibers and one of its considerable aspects, nowadays, is that this kind of cellulose is used as a drug carrier system for treating various diseases. Azithromycin is used as an antibiotic for the treatment of a wide range of bacterial infections. In this study, cellulose nanofibers were synthesized by gluconacetobacter and its surface was modified using 0.5, 1, and 1.5 mg/ml carboxymethylcellulose solution in sodium acetate buffer. Then, by stabilizing azithromycin... 

    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) Pourjavadi, A ; Ghasemzadeh, H ; Sharif University of Technology
    Rapra Technology Ltd  2006
    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... 

    Evaluation of cellular attachment and proliferation on different surface charged functional cellulose electrospun nanofibers

    , Article Carbohydrate Polymers ; Volume 207 , 2019 , Pages 796-805 ; 01448617 (ISSN) Golizadeh, M ; Karimi, A ; Gandomi Ravandi, S ; Vossoughi, M ; Khafaji, M ; Joghataei, M. T ; Faghihi, F ; Sharif University of Technology
    Elsevier Ltd  2019
    Fabrication and characterization of different surface charged cellulose electrospun scaffolds including cellulose acetate (CA), cellulose, carboxymethyl cellulose (CMC) and quaternary ammonium cationic cellulose (QACC) for biomedical applications have been reported in this research. Several instrumental techniques were employed to characterize the nanofibers. MTT assay and cell attachment studies were also carried out to determine the cytocompatibility, viability and proliferation of the scaffolds. Fabricated CA, cellulose, CMC and QACC nanofibers had 100–600 nm diameter, −9, −1.75, −12.8, + 22 mV surface potential, 2.5, 4.2, 7.2, 7 MPa tensile strength, 122, 320, 515, 482 MPa Young modules,... 

    Synthesis & Characterization of All-Cellulose Nanocomposites Containing Natural Extracts for Smart Packaging Applications

    , M.Sc. Thesis Sharif University of Technology Azizi Saadatlou, Ghazaleh (Author) ; Pircheraghi, Gholamreza (Supervisor)
    In this project, all-cellulose nanocomposites for smart packaging of meat products were synthesized via film casing method. These nanocomposites were aimed to provide visual response to pH change, which occurs due to decay of the meat products. The prepared nanocomposites would be placed inside the packages to be in direct contact with the products and could improve shelf life the products with the help of antibacterial natural extracts incorporated in the samples.Synthesis of the samples started with cellulose nano whiskers synthesis via acid hydrolysis. The prepared nanoparticles were then characterized with XRD, DLS, and Zeta potential analysis. It was shown that a big portion of the... 

    Investigating morphology and performance of cellulose acetate butyrate electrospun nanofiber membranes for tomato industry wastewater treatment

    , Article Desalination and Water Treatment ; Volume 64 , 2017 , Pages 127-135 ; 19443994 (ISSN) Hosseini, S. A ; Soltanieh, M ; Mousavi, S. M ; Sharif University of Technology
    Desalination Publications  2017
    In this research, cellulose acetate butyrate (CAB) electrospun nanofiber membrane (ENM) was prepared by electrospinning method in order to separate the contaminants of an industrial wastewater. The influence of various electrospinning parameters on morphology and average fiber diameter of the membranes were investigated by scanning electron microscopy and image analysis. The permeability of the membranes was evaluated by measuring pure water flux. In order to investigate the performance of the prepared membranes for tomato wastewater treatment, the rejection of the pollution indices and flux were determined. The results demonstrated the potential of using CAB nanofiber membrane for... 

    Development of chitosan/bacterial cellulose composite films containing nanodiamonds as a potential flexible platform for wound dressing

    , Article Materials ; Volume 8, Issue 9 , 2015 , Pages 6401-6418 ; 19961944 (ISSN) Ostadhossein, F ; Mahmoudi, N ; Morales Cid, G ; Tamjid, E ; Navas Martos, F. J ; Soriano Cuadrado, B ; Paniza, J. M. L ; Simchi, A ; Sharif University of Technology
    MDPI AG  2015
    Chitosan/bacterial cellulose composite films containing diamond nanoparticles (NDs) with potential application as wound dressing are introduced. Microstructural studies show that NDs are uniformly dispersed in the matrix, although slight agglomeration at concentrations above 2 wt % is seen. Fourier transform infrared spectroscopy reveals formation of hydrogen bonds between NDs and the polymer matrix. X-ray diffraction analysis indicates reduced crystallinity of the polymer matrix in the presence of NDs. Approximately 3.5-fold increase in the elastic modulus of the composite film is obtained by the addition of 2 wt % NDs. The results of colorimetric analysis show that the composite films are... 

    Evaluation of prepared natural polymers in the extraction of chlorobenzenes from environmental samples: sol–gel–based cellulose acetate-phenyltriethoxysilane fibers

    , Article Microchemical Journal ; Volume 142 , 2018 , Pages 265-272 ; 0026265X (ISSN) Bagheri, H ; Golzari Aqda, T ; Enteshari Najafabadi, M ; Sharif University of Technology
    In this research, three fibers including cellulose acetate (CA), CA–phenyltriethoxysilane (PTES) prepared via sol–gel electrospinning and sol–gel–based CA fibers immersed in PTES solution (dipped–CA–PTES) were prepared. The composition and morphology of the prepared fibers were evaluated by energy dispersive X-ray spectroscopy and field emission scanning electron microscopy. The prepared fibers were implemented in a home–made needle trap device, followed by thermal desorption of the selected chlorobenzenes (CBs) to a gas chromatography–flame ionization detector. Finally, parameters affecting the extraction methodology such as the amount of sorbent, extraction time and temperature, desorption... 

    Cellulose acetate/magnetic graphene nanofiber in enhanced human mesenchymal stem cells osteogenic differentiation under alternative current magnetic field

    , Article SPIN ; Volume 9, Issue 2 , 2019 ; 20103247 (ISSN) Hatamie, S ; Mohamadyar Toupkanlou, F ; Mirzaei, S ; Ahadian, M. M ; Hosseinzadeh, S ; Soleimani, M ; Sheu, W. J ; Wei, Z. H ; Hsieh, T. F ; Chang, W. C ; Wang, C. L ; Sharif University of Technology
    World Scientific Publishing Co. Pte Ltd  2019
    The three-dimensional (3D) nano scaffold of the cellulose acetate (CA) containing graphene/cobalt nanocomposite (0.1wt.%) was fabricated via electrospinning technique, and its impact on bone regeneration was investigated. Through this aim, bone marrow mesenchymal stem cells are cultured on the CA, and graphene/cobalt (rGO/Co)/CA nanocomposite scaffold surfaces and the samples are treated under low frequency alternative magnetic field (75Hz). The scaffolds are characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and thermal studies (TG/DSC). The proliferation behavior of stem cells on CA, and rGO/Co/CA nano scaffolds are studied by MTT assay, show their... 

    Pressure-engineered electrophoretic deposition for gentamicin loading within osteoblast-specific cellulose nanofiber scaffolds

    , Article Materials Chemistry and Physics ; Volume 272 , 2021 ; 02540584 (ISSN) Rahighi, R ; Panahi, M ; Akhavan, O ; Mansoorianfar, M ; Sharif University of Technology
    Elsevier Ltd  2021
    Multi-component nanocomposite thin films (composed of cellulose nanofiber (CNF), alginate, bioglass nanoparticles (BG NPs) and gentamicin) were prepared by using cathodic electrophoretic deposition (EPD) under different isostatic pressures of 10−2 mbar (LP), atmospheric (AP), and 5 bar (HP). According to thermal gravity analysis, larger amounts of CNF and alginate could be deposited on the surface at the AP condition in comparison with the LP and HP conditions. On the other hand, higher amounts of the BG NPs could be deposited at the LP condition as compared to the other conditions. The drug (gentamicin) loading/releasing of the samples prepared at the HP condition was found to be higher... 

    Modified CMC. 3. Carboxymethylcellulose-g-poly(acrylamidrazone) as a new metal adsorbent

    , Article Journal of Polymer Materials ; Volume 21, Issue 3 , 2004 , Pages 315-320 ; 09738622 (ISSN) Zohuriaan Mehr, M. J ; Pourjavadi, A ; Salehi Rad, M ; Sharif University of Technology
    A new poly(acrylamidrazone) chelating resin was prepared from carboxymethylcellulose (CMC) via a two-step process. First, acrylonitrile was graft polymerized onto the substrate. The CMC-polyacrylonitrile graft copolymer was then treated with hydrazine to yield a triply modified cellulose containing amidrazone functional groups. The resin was characterized using infrared spectroscopy. The sorption capacity of the resin towards bivalent metal ions was evaluated versus variation of pH and hydrochloric acid concentration. The adsorption capacities at pH 6 were found to be in order Cu2+> Zn2+>Cd2+>Co2+>Ni2+. The metal ion sorption capacities were varied in the range of 2.0-20.0 mmol metal per... 

    Nano composite coating based on cellulose nanofibers/carbon nanoparticles: application to voltammetric determination of clonazepam

    , Article Journal of Solid State Electrochemistry ; Vol. 19, issue. 1 , 2014 , p. 251-260 Shahrokhian, S ; Balotf, H ; Ghalkhani, M ; Sharif University of Technology
    A novel electrochemical sensor for clonazepam (CLNP) was fabricated based on immobilizing cellulose nanofibers/carbon nanoparticles (CNFs/CNPs) nanocomposite on glassy carbon electrode (CNFs/CNPs/GCE). The combination of CNFs and CNPs produced a novel kind of structurally uniform and electro-analytically active nanocomposite. The surface morphology of CNFs/CNPs layer deposited onto glassy carbon electrode was characterized by scanning electron microscopy. The results of the voltammetric investigations showed a considerable enhancement in the cathodic peak current of CLNP (up to 60 times) on the surface of CNFs/CNPs/GCE relative to the bare GCE. Under the optimal conditions, the modified... 

    Photo-induced growth of silver nanoparticles using UV sensitivity of cellulose fibers

    , Article Applied Surface Science ; Volume 258, Issue 7 , 2012 , Pages 2373-2377 ; 01694332 (ISSN) Omrani, A. A ; Taghavinia, N ; Sharif University of Technology
    A simple method has been demonstrated to grow silver nanoparticles on the surface of cellulose fibers. The preparation is based on photo-activation of surface by ultraviolet (UV) photons, followed by chemical reduction of silver nitrate. It is found that the concentration of silver nitrate in the solution is not a determining factor, while UV intensity affects the rate of initial growth and determines the final concentration of the loaded silver. We explain the phenomena based on a model including the number of reducing sites on the surface of cellulose fibers activated by UV photons, and a release mechanism that causes a slow rate of dissolution of silver back into the solution  

    Stable dye-sensitized solar cells based on a gel electrolyte with ethyl cellulose as the gelator

    , Article Applied Physics A: Materials Science and Processing ; Volume 120, Issue 3 , September , 2015 , Pages 869-874 ; 09478396 (ISSN) Vasei, M ; Tajabadi, F ; Jabbari, A ; Taghavinia, N ; Sharif University of Technology
    Springer Verlag  2015
    A simple gelating process is developed for the conventional acetonitrile-based electrolyte of dye solar cells, based on ethyl cellulose as the gelator. The electrolyte becomes quasi-solid-state upon addition of an ethanolic solution of ethyl cellulose to the conventional acetonitrile-based liquid electrolyte. The photovoltaic conversion efficiency with the new gel electrolyte is only slightly lower than with the liquid electrolyte, e.g., 6.5 % for liquid electrolyte versus 5.9 % for gel electrolyte with 5.8 wt% added ethyl cellulose. Electrolyte gelation has small effect on the ionic diffusion coefficient of iodide, and the devices are remarkably stable for at least 550 h under irradiation... 

    Cellulose-immobilized NHC-Cu(i) complex: An efficient and reusable catalyst for multicomponent synthesis of 1,2,3-triazoles

    , Article RSC Advances ; Volume 5, Issue 120 , Nov , 2015 , Pages 99498-99501 ; 20462069 (ISSN) Pourjavadi, A ; Habibi, Z ; Sharif University of Technology
    Royal Society of Chemistry  2015
    A novel cellulose supported copper NHC complex has been prepared by the reaction of cellulose supported imidazolium salt with copper(i) iodide. The catalyst is active in the synthesis of 1,2,3-triazoles via a one-pot reaction of alkyl/benzyl halides or tosylates and terminal alkynes, with sodium azide in water  

    Electrospinning of nanodiamond-modified polysaccharide nanofibers with physico-mechanical properties close to natural skins

    , Article Marine Drugs ; Volume 14, Issue 7 , 2016 ; 16603397 (ISSN) Mahdavi, M ; Mahmoudi, N ; Rezaie Anaran, F ; Simchi, A ; Sharif University of Technology
    MDPI AG 
    Electrospinning of biopolymers has gained significant interest for the fabrication of fibrous mats for potential applications in tissue engineering, particularly for wound dressing and skin regeneration. In this study, for the first time, we report successful electrospinning of chitosan-based biopolymers containing bacterial cellulous (33 wt %) and medical grade nanodiamonds (MND) (3 nm; up to 3 wt %). Morphological studies by scanning electron microscopy showed that long and uniform fibers with controllable diameters from 80 to 170 nm were prepared. Introducing diamond nanoparticles facilitated the electrospinning process with a decrease in the size of fibers. Fourier transform infrared...