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Voltammetric studies of sumatriptan on the surface of pyrolytic graphite electrode modified with multi-walled carbon nanotubes decorated with silver nanoparticles
, Article Talanta ; Volume 80, Issue 1 , 2009 , Pages 31-38 ; 00399140 (ISSN) ; Shahrokhian, S ; Ghorbani Bidkorbeh, F ; Sharif University of Technology
2009
Abstract
Multi-walled carbon nanotube decorated with silver nanoparticles (AgNPs-MWCNT) is used as an effective strategy for modification of the surface of pyrolytic graphite electrode (PGE). This modification procedure improved colloidal dispersion of the decorated MWCNTs in water, affording uniform and stable thin films for altering the surface properties of the working electrode. Robust electrode for sensing applications is obtained in a simple solvent evaporation process. The electrochemical behavior of sumatriptan (Sum) at the bare PGE and AgNPs-MWCNT modified PGE is investigated. The results indicate that the AgNPs-MWCNT modified PGE significantly enhanced the oxidation peak current of Sum. A...
Useful multivariate kinetic analysis: Size determination based on cystein-induced aggregation of gold nanoparticles
, Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 115 , 2013 , Pages 588-594 ; 13861425 (ISSN) ; Nezhad, M. R. H ; Abdollahi, H ; Sharif University of Technology
2013
Abstract
This study describes spectrometric monitored kinetic processes to determine the size of citrate-capped Au nanoparticles (Au NPs) based on aggregation induced by L-cysteine (L-Cys) as a molecular linker. The Au NPs association process is thoroughly dependent on pH, concentration and size of nanoparticles. Size dependency of aggregation inspirits to determine the average diameters of Au NPs. For this aim the procedure is achieved in aqueous medium at pH 7 (phosphate buffer), and multivariate data including kinetic spectra of Au NPs are collected during aggregation process. Subsequently partial least squares (PLS) modeling is carried out analyzing the obtained data. The model is built on the...
TiO2 nanofibre assisted photocatalytic degradation of reactive blue 19 dye from aqueous solution
, Article Environmental Technology ; Volume 30, Issue 3 , 2009 , Pages 233-239 ; 09593330 (ISSN) ; Ghaneian, M. T ; Taghavinia, N ; Khajeh Aminian, M ; Hashemian, S. J ; Sharif University of Technology
2009
Abstract
The photocatalytic degradation of Reactive Blue 19 (RB19) dye has been studied using TiO2 nanofibre as the photocatalyst in aqueous solution under UV irradiation. Titanium dioxide nanofibre was prepared using a templating method with tetraisopropylorthotitanate as a precursor. The experiments were carried out in the presence of the TiO2 nanofibre, and the effects of pH and electron acceptors on the degradation process were investigated. In order to observe the quality of the aqueous solution, chemical oxygen demand (COD) measurements were also carried out before and after the treatments. The photocatalytic decomposition of RB19 was most efficient in acidic solution. With the addition of...
The two-step thermochemical growth of ZnS:Mn nanocrystals and a study of luminescence evolution
, Article Nanotechnology ; Volume 20, Issue 9 , 2009 ; 09574484 (ISSN) ; Marandi, M ; Taghavinia, N ; Houshiar, M ; Sharif University of Technology
2009
Abstract
In this work we report a new thermochemical method for the synthesis of ZnS:Mn nanocrystals. Zn(NO3)2 and Na2S 2O3 were used as the precursors and Mn(NO 3)2 was the source of impurity. Thioglycerol (TG,C 3H8O2S) was also used as the capping agent and the catalyst of the reaction. Na2S2O3 is a heat sensitive material which releases S species upon heating. Consequently, the reaction proceeds in temperatures higher than room temperature. The reaction was done in two steps. In the first step, the precursors were heated at 96 °C for an hour without TG. In the second step, TG was injected to the solution and the heating process was continued for longer heating durations. A fast growth occurred in...
Temporary skin grafts based on hybrid graphene oxide-natural biopolymer nanofibers as effective wound healing substitutes: pre-clinical and pathological studies in animal models
, Article Journal of Materials Science: Materials in Medicine ; Volume 28, Issue 5 , 2017 , 73 ; 09574530 (ISSN) ; Eslahi, N ; Mehdipour, A ; Mohammadi, M ; Akbari, M ; Samadikuchaksaraei, A ; Simchi, A ; Sharif University of Technology
Springer New York LLC
2017
Abstract
Abstract: In recent years, temporary skin grafts (TSG) based on natural biopolymers modified with carbon nanostructures have received considerable attention for wound healing. Developments are required to improve physico-mechanical properties of these materials to match to natural skins. Additionally, in-deep pre-clinical examinations are necessary to ensure biological performance and toxicity effect in vivo. In the present work, we show superior acute-wound healing effect of graphene oxide nanosheets embedded in ultrafine biopolymer fibers (60 nm) on adult male rats. Nano-fibrous chitosan-based skin grafts crosslinked by Genepin with physico-mechanical properties close to natural skins were...
Synthesis of nanostructured Ag@SiO2-Penicillin from high purity Ag NPs prepared by electromagnetic levitation melting process
, Article Materials Science and Engineering C ; Volume 102 , 2019 , Pages 616-622 ; 09284931 (ISSN) ; Yeung, K. L ; Halali, M ; Chang, Q ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
Nanostructured Ag@SiO2-Penicillin was synthesized from high-purity Ag0 NPs with a mean particle size of about 10 nm produced by electromagnetic levitation gas condensation (ELGC) method. The silver and penicillin contents of the synthesized nano-antibiotic were about 34 wt% and 2.5 wt% respectively, as determined by ICP-OES and TGA analyses. The antibacterial properties and synergistic effects of nanostructured Ag@SiO2 and Ag@SiO2–Penicillin on killing the Methicillin-susceptible S. aureus (MSSA) and Methicillin-resistant S. aureus (MRSA) bacteria were also examined. The nanoparticles were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Ag@SiO2-Penicillin...
Synthesis of cellulose acetate/chitosan/SWCNT/Fe3O4/TiO2 composite nanofibers for the removal of Cr(VI), As(V), Methylene blue and Congo red from aqueous solutions
, Article International Journal of Biological Macromolecules ; Volume 140 , 2019 , Pages 1296-1304 ; 01418130 (ISSN) ; Koushkbaghi, S ; Pishnamazi, M ; Askari, A ; Khosravi, R ; Irani, M ; Sharif University of Technology
Elsevier B.V
2019
Abstract
The potential of electrospun cellulose acetate/chitosan/single walled carbon nanotubes/ferrite/titanium dioxide (CA/chitosan/SWCNT/Fe3O4/TiO2) nanofibers was investigated for the removal of Cr(VI), As(V), Methylene blue and Congo red from aqueous solutions via the adsorption and photocatalytic reduction processes. The properties of synthesized SWCNT/Fe3O4/TiO2 and fibers were characterized using TEM, SEM, FTIR, XRD, TGA and BET analysis. In adsorption process, the influence of adsorbent type including SWCNT to Fe3O4 ratio, TiO2 to SWCNT/Fe3O4 ratio and SWCNT/Fe3O4/TiO2 concentration as well as the adsorption parameters including pH, contact time, and initial concentration of adsorbates on...
Synthesis and characterization of gold nanotube/nanowire-polyurethane composite based on castor oil and polyethylene glycol
, Article Materials Science and Engineering C ; Vol. 42 , 2014 , pp. 341-349 ; ISSN: 09284931 ; Kasra,M ; Salahshour Kordestani, S ; Bagheri Hariri, M ; Sharif University of Technology
Abstract
Gold nanotubes/nanowires (GNT/NW) were synthesized by using the template-assisted electrodeposition technique and mixed with castor oil-polyethylene glycol based polyurethane (PU) to fabricate porous composite scaffolds for biomedical application. 100 and 50 ppm of GNT/NW were used to synthesize composites. The composite scaffolds were characterized by Fourier transform infrared spectroscopy, dynamic mechanical thermal analysis, differential scanning calorimetry, and scanning electron microscopy. Cell attachment on polyurethane-GNT/NW composites was investigated using fat-derived mesenchymal stem cells. Addition of 50 or 100 ppm GNT/NW had significant effects on thermal, mechanical, and cell...
Structural stability and sustained release of protein from a multilayer nanofiber/nanoparticle composite
, Article International Journal of Biological Macromolecules ; Volume 75 , April , 2015 , Pages 248-257 ; 01418130 (ISSN) ; Mashayekhan, S ; Shabani, I ; Khorashadizadeh, M ; Fallah, A ; Soleimani, M ; Sharif University of Technology
Elsevier
2015
Abstract
The cellular microenvironment can be engineered through the utilization of various nano-patterns and matrix-loaded bioactive molecules. In this study, a multilayer system of electrospun scaffold containing chitosan nanoparticles was introduced to overcome the common problems of instability and burst release of proteins from nanofibrous scaffolds. Bovine serum albumin (BSA)-loaded chitosan nanoparticles was fabricated based on ionic gelation interaction between chitosan and sodium tripolyphosphate. Suspension electrospinning was employed to fabricate poly-e{open}-caprolacton (PCL) containing protein-loaded chitosan nanoparticles with a core-shell structure. To obtain the desired scaffold...
Simultaneous controlled release of 5-FU, DOX and PTX from chitosan/PLA/5-FU/g-C3N4-DOX/g-C3N4-PTX triaxial nanofibers for breast cancer treatment in vitro
, Article Colloids and Surfaces B: Biointerfaces ; Volume 179 , 2019 , Pages 495-504 ; 09277765 (ISSN) ; Hosseini, S ; Mahboobnia, K ; Boloursaz, L. A ; Moradi, M ; Irani, M ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In the present study, the tri-layer nanofibers were synthesized via triaxial electrospinning process to control the sustained delivery of Doxorubicin (DOX), Paclitaxel (PTX) and 5- fluorouracil (5-FU) anticancer drugs from nanofibers. The 5-FU molecules were incorporated into the core solution (chitosan/polyvinyl alcohol (CS/PVA)) to fabricate the CS/PVA/5-FU inner layer of nanofibers. The intermediate layer was prepared from poly(lactic acid)/chitosan (PLA/CS) nanofibers. The DOX and PTX molecules were initially loaded into the g-C3N4 nanosheets and following were incorporated into the PLA/CS solution to fabricate the outer layer of nanofibers. The synthesized nanosheets and nanofibers were...
Roles of inorganic oxide nanoparticles on extraction efficiency of electrospun polyethylene terephthalate nanocomposite as an unbreakable fiber coating
, Article Journal of Chromatography A ; Volume 1375 , 2015 , Pages 8-16 ; 00219673 (ISSN) ; Roostaie, A ; Sharif University of Technology
Elsevier
2015
Abstract
In the present work, the roles of inorganic oxide nanoparticles on the extraction efficiency of polyethylene terephthalate-based nanocomposites were extensively studied. Four fiber coatings based on polyethylene terephthalate nanocomposites containing different types of nanoparticles along with a pristine polyethylene terephthalate polymer were conveniently electrospun on stainless steel wires. The applicability of new fiber coatings were examined by headspace-solid phase microextraction of some environmentally important volatile organic compound such as benzene, toluene, ethylbenzene and xylene (BTEX), as model compounds, from aqueous samples. Subsequently, the extracted analytes were...
Pyrolytic carbon coating for cytocompatibility of titanium oxide nanoparticles: A promising candidate for medical applications
, Article Nanotechnology ; Volume 23, Issue 4 , 2012 ; 09574484 (ISSN) ; Imani, M ; Yousefi, M ; Galinetto, P ; Simchi, A ; Amiri, H ; Stroeve, P ; Mahmoudi, M ; Sharif University of Technology
2012
Abstract
Nanoparticles for biomedical use must be cytocompatible with the biological environment that they are exposed to. Current research has focused on the surface functionalization of nanoparticles by using proteins, polymers, thiols and other organic compounds. Here we show that inorganic nanoparticles such as titanium oxide can be coated by pyrolytic carbon (PyC) and that the coating has cytocompatible properties. Pyrolization and condensation of methane formed a thin layer of pyrolytic carbon on the titanium oxide core. The formation of the PyC shell retards coalescence and sintering of the ceramic phase. Our MTT assay shows that the PyC-coated particles are cytocompatible at employed doses
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...
Preparation and characterization of multi-walled carbon nanotube/hydroxyapatite nanocomposite film dip coated on Ti-6Al-4V by sol-gel method for biomedical applications: An in vitro study
, Article Materials Science and Engineering C ; Volume 33, Issue 4 , 2013 , Pages 2002-2010 ; 09284931 (ISSN) ; Hooshmand, T ; Mohammadi, M ; Najafi, F ; Sharif University of Technology
2013
Abstract
In the present research, the introduction of multi-walled carbon nanotubes (MWCNTs) into the hydroxyapatite (HA) matrix and dip coating of nanocomposite on titanium alloy (Ti-6Al-4V) plate was conducted in order to improve the performance of the HA-coated implant via the sol-gel method. The structural characterization and electron microscopy results confirmed well crystallized HA-MWCNT coating and homogenous dispersion of carbon nanotubes in the ceramic matrix at temperatures as low as 500 C. The evaluation of the mechanical properties of HA and HA/MWCNT composite coatings with different weight percentages of MWCNTs showed that the addition of low concentrations of MWCNTs (0.5 and 1 wt.%)...
Polyphenols attached graphene nanosheets for high efficiency NIR mediated photodestruction of cancer cells
, Article Materials Science and Engineering C ; Volume 33, Issue 3 , 2013 , Pages 1498-1505 ; 09284931 (ISSN) ; Janmaleki, M ; Mohajerzadeh, S ; Akhavan, O ; Abbasi, S ; Sharif University of Technology
2013
Abstract
Green tea-reduced graphene oxide (GT-rGO) sheets have been exploited for high efficiency near infrared (NIR) photothermal therapy of HT29 and SW48 colon cancer cells. The biocompatibility of GT-rGO sheets was investigated by means of MTT assays. The polyphenol constituents of GT-rGO act as effective targeting ligands for the attachment of rGO to the surface of cancer cells, as confirmed by the cell granularity test in flow cytometry assays and also by scanning electron microscopy. The photo-thermal destruction of higher metastatic cancer cells (SW48) is found to be more than 20% higher than that of the lower metastatic one (HT29). The photo-destruction efficiency factor of the GT-rGO is...
Pd-Au nanoparticle decorated carbon nanotube as a sensing layer on the surface of glassy carbon electrode for electrochemical determination of ceftazidime
, Article Materials Science and Engineering C ; Vol. 34, issue. 1 , 2014 , pp. 318-325 ; ISSN: 09284931 ; Salimian, R ; Rastgar, S ; Sharif University of Technology
Abstract
A simple electrodeposition method is employed to construct a thin film modifier of palladium-gold nanoparticles (Pd-AuNPs) decorated multi-walled carbon nanotube (MWCNT) on the surface of glassy carbon electrode (GCE). Morphology and property of Pd-AuNPs-MWCNT have been examined by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Electrochemical performance of Pd-AuNPs-MWCNT/GCE for detection of ceftazidime (CFZ) has been investigated by cyclic voltammetry (CV). This nanostructured film modified electrode effectively exhibited enhanced properties for detection of ceftazidime (CFZ). The effects of various experimental variables such as, the amount of casted MWCNT,...
Nanoscale characterization of the biomolecular corona by cryo-electron microscopy, cryo-electron tomography, and image simulation
, Article Nature Communications ; Volume 12, Issue 1 , 2021 ; 20411723 (ISSN) ; Basu, K ; Farnudi, A ; Ashkarran, A ; Ichikawa, M ; Presley, J. F ; Bui, K. H ; Ejtehadi, M. R ; Vali, H ; Mahmoudi, M ; Sharif University of Technology
Nature Research
2021
Abstract
The biological identity of nanoparticles (NPs) is established by their interactions with a wide range of biomolecules around their surfaces after exposure to biological media. Understanding the true nature of the biomolecular corona (BC) in its native state is, therefore, essential for its safe and efficient application in clinical settings. The fundamental challenge is to visualize the biomolecules within the corona and their relationship/association to the surface of the NPs. Using a synergistic application of cryo-electron microscopy, cryo-electron tomography, and three-dimensional reconstruction, we revealed the unique morphological details of the biomolecules and their...
Nanomechanical properties of TiO2 granular thin films
, Article ACS Applied Materials and Interfaces ; Volume 2, Issue 9 , 2010 , Pages 2629-2636 ; 19448244 (ISSN) ; Taghavinia, N ; Keshavarz Alamdari, E ; Volinsky, A.A ; Sharif University of Technology
2010
Abstract
Post-deposition annealing effects on nanomechanical properties of granular TiO2 films on soda-lime glass substrates were studied. In particular, the effects of Na diffusion on the films' mechanical properties were examined. TiO2 photocatalyst films, 330 nm thick, were prepared by dip-coating using a TiO2 sol, and were annealed between 100 °C and 500 °C. Film's morphology, physical and nanomechanical properties were characterized by atomic force microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, differential thermo-gravimetric analysis, and nanoindentation. Contrary to expectations, the maximum film hardness was achieved for 300°C annealing, with a value of 0.69 ± 0.05 GPa....
Nanofibrillated chitosan coated highly ordered titania nanotubes array/graphene nanocomposite with improved biological characters
, Article Carbohydrate Polymers ; Volume 254 , 2021 ; 01448617 (ISSN) ; Bagheri, R ; Heidarpour, H ; Vossoughi, M ; Golizadeh, M ; Samadikuchaksaraei, A ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Designing multifunctional surfaces is key to develop advanced materials for orthopedic applications. In this study, we design a double-layer coating, assembled onto the completely regular titania nanotubes (cRTNT) array. Benefiting from the biological and topological characteristics of chitosan nanofibers (CH) and reduced graphene oxide (RGO) through a unique assembly, the designed material features promoted osteoblast cell viability, prolonged antibiotic release profile, as well as inhibited bacterial biofilm formation. The synergistic effect of RGO and CH on the biological performance of the surface is investigatSed. The unique morphology of the nanofibers leads to the partial coverage of...
Mechanical reinforcement of urinary bladder matrix by electrospun polycaprolactone nanofibers
, Article Scientia Iranica ; Volume 24, Issue 6 , 2017 , Pages 3476-3480 ; 10263098 (ISSN) ; Rajabi Zeleti, S ; Naji, M ; Ghanian, M. H ; Baharvand, H ; Sharif University of Technology
Abstract
For a successful repair and reconstruction of bladder tissue, fabrication of scaffolds with proper biochemical and biomechanical characteristics is necessary. Decellularized bladder tissue has been proposed in previous studies as a gold standard material for scaffold fabrication. However, weak mechanical properties of such a load-bearing tissue has remained a challenge. Incorporation of both biological and synthetic materials has been known as an effective strategy for improving mechanical and biological properties of the scaffolds. In the present work, a simple process was developed to fabricate hybrid hydrogel scaffolds with a biomimetic architecture from the natural urinary bladder...