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    Rosmarinus officinalis directed palladium nanoparticle synthesis: Investigation of potential anti-bacterial, anti-fungal and Mizoroki-Heck catalytic activities

    , Article Advanced Powder Technology ; Volume 31, Issue 4 , 2020 , Pages 1402-1411 Rabiee, N ; Bagherzadeh, M ; Kiani, M ; Ghadiri, A. M ; Sharif University of Technology
    Elsevier B.V  2020
    The present work was aimed to account a green and eco-friendly synthesis of palladium nanoparticles using Rosmarinus officinalis leaves extracts for the first time, therefore, that can be an acceptable replacement for chemical media to improve potential biological properties. The synthesized palladium nanoparticles were fully characterized using FT-IR, XRD, FESEM, TEM and UV/Vis spectroscopy techniques. Catalytic activity was investigated by Mizoroki-Heck reaction, and optimized based on solvent, temperature and time of the reaction, and the best results were found in water as a green media without any additional reagents. Biological activity of the synthesized nanoparticles were evaluated... 

    Graphene oxide sheets involved in vertically aligned zinc oxide nanowires for visible light photoinactivation of bacteria

    , Article Journal of Alloys and Compounds ; Vol. 612 , 2014 , pp. 380-385 ; ISSN: 09258388 Nourmohammadi, A ; Rahighi, R ; Akhavan, O ; Moshfegh, A ; Sharif University of Technology
    Vertically aligned ZnO nanowires (NWs) hybridized with reduced graphene oxide sheets (rGO) were applied in efficient visible light photoinactivation of bacteria. To incorporate graphene oxide (GO) sheets within the NWs two different methods of drop-casting and electrophoretic deposition (EPD) were utilized. The EPD method yielded effective penetration of the positively charged GO sheets into the NWs to form a spider net-like structure, whereas the drop-casting method resulted in only a surface coverage of the GO sheets on top of the NWs. The electrical connection between the EPD-incorporated sheets and the NWs was checked by monitoring the electron transfer from UV-assisted photoexcited ZnO... 

    Visible light photoinactivation of bacteria by tungsten oxide nanostructures formed on a tungsten foil

    , Article Applied Surface Science ; Volume 338 , May , 2015 , Pages 55-60 ; 01694332 (ISSN) Ghasempour, F ; Azimirad, R ; Amini, A ; Akhavan, O ; Sharif University of Technology
    Elsevier  2015
    Antibacterial activity of tungsten oxide nanorods/microrods were studied against Escherichia coli bacteria under visible light irradiation and in dark. A two-step annealing process at temperatures up to 390 °C and 400-800 °C was applied to synthesize the tungsten oxide nanorods/microrods on tungsten foils using KOH as a catalyst. Annealing the foils at 400 °C in the presence of catalyst resulted in formation of tungsten oxide nanorods (with diameters of 50-90 nm and crystalline phase of WO3) on surface of tungsten foils. By increasing the annealing temperature up to 800 °C, tungsten oxide microrods with K2W6O19 crystalline phase were formed on the foils. The WO3 nanorods showed a strong... 

    Investigation of metal absorption and antibacterial activity on cotton fabric modified by low temperature plasma

    , Article Cellulose ; Volume 17, Issue 3 , 2010 , Pages 627-634 ; 09690239 (ISSN) Shahidi, S ; Rashidi, A ; Ghoranneviss, M ; Anvari, A ; Rahimi, M. K ; Bameni Moghaddam, M ; Wiener, J ; Sharif University of Technology
    In this work, the silver particle absorption and antibacterial activity of cotton fabric when modified by low temperature plasma were investigated. The modification consisted of plasma pre-functionalization followed by one-step wet treatment with silver nitrate solution. Oxygen and nitrogen were used as the working gases in the system, and the results were compared. The results showed that nitrogen plasma-treated samples can absorb more silver particles than oxygen-treated samples, and thus the antibacterial activity of the samples in this case, which was analyzed by the counting bacteria test, was increased considerably  

    Smart and fragrant garment via surface modification of cotton fabric with cinnamon oil/stimuli responsive PNIPAAm/chitosan nano hydrogels

    , Article IEEE Transactions on Nanobioscience ; Volume 16, Issue 6 , 2017 , Pages 455-462 ; 15361241 (ISSN) Bashari, A ; Hemmatinejad, N ; Pourjavadi, A ; Sharif University of Technology
    This paper deals with obtaining aromatherapic textiles via applying stimuli-responsive poly N-isopropyl acryl amide (PNIPAAm) chitosan (PNCS) nano hydrogels containing cinnamon oil on cotton fabric and looks into the treated fabric characteristics as an antibacterial and temperaturepH responsive fabric. The semi-batch surfactant-free dispersion polymerization method was proposed to the synthesis of PNCS nano particles. The incorporation of modified β -cyclodextrin ( β-CD) into the PNCS nanohydrogel was performed in order to prepare a hydrophobic(cinnamon oil) carrier embedded in stimuli-responsive nanohydrogel. The β -CD postloading process of cinnamon oil in to the hydrogel nano particles... 

    Sustainable release of vancomycin from silk fibroin nanoparticles for treating severe bone infection in rat tibia osteomyelitis model

    , Article ACS Applied Materials and Interfaces ; Volume 9, Issue 6 , 2017 , Pages 5128-5138 ; 19448244 (ISSN) Hassani Besheli, N ; Mottaghitalab, F ; Eslami, M ; Gholami, M ; Kundu, S. C ; Kaplan, D. L ; Farokhi, M ; Sharif University of Technology
    American Chemical Society  2017
    The successful treatment of bone infections is a major challenge in the field of orthopedics. There are some common methods for treating bone infections, including systemic antibiotic administration, local nondegradable drug vehicles, and surgical debridement, and each of these approaches has advantages and disadvantages. In the present study, the antibiotic vancomycin (VANCO) was loaded in silk fibroin nanoparticles (SFNPs) and the complexes were then entrapped in silk scaffolds to form sustained drug delivery systems. The release kinetics of VANCO from SFNPs alone and when the SFNPs were entrapped in silk scaffolds were assessed at two different pH values, 4.5 and 7.4, that affected the... 

    Zeolite-based catalytic micromotors for enhanced biological and chemical water remediation

    , Article New Journal of Chemistry ; Volume 44, Issue 44 , 2020 , Pages 19212-19219 Abedini, F ; Madaah Hosseini, H. R ; Sharif University of Technology
    Royal Society of Chemistry  2020
    Zeolite-based micromotors were developed to eliminate the biological and chemical contamination of water in a fast and efficient way. The motors consist of a silver-exchanged zeolite core and a partial catalytic coating. These porous engines showed rapid killing of Pseudomonas aeruginosa bacteria cells in a very short time, less than 7.5 minutes. The heavy metal uptake of the zeolitic motors during the first 20 minutes of contact was considerably higher than that of zeolite particles by 23% for Pb2+, 19% for Co2+, and 16% for Ni2+. Also, the maximum removal efficiency of the motors (at room temperature and for 6 hours) for Pb2+, Co2+, and Ni2+ was 93%, 87%, and 78%, respectively, higher than... 

    Green synthesis of CuO- And Cu2O-NPs in assistance with high-gravity- And flowering of nanobiotechnology

    , Article Nanotechnology ; Volume 31, Issue 42 , 2020 Ghadiri, A. M ; Rabiee, N ; Bagherzadeh, M ; Kiani, M ; Fatahi, Y ; Di Bartolomeo, A ; Dinarvand, R ; Webster, T. J ; Sharif University of Technology
    Institute of Physics Publishing  2020
    This study, for the first time, reports the synthesis of CuO- and Cu2O nanoparticles (NPs) using the Salvia hispanica extract by a high-gravity technique. The original green synthesis procedure led to the formation of nanoparticles with promising catalytic and biological properties. The synthesized nanoparticles were fully characterized and their catalytic activity was evaluated through a typical Azide-Alkyne Cycloaddition (AAC) reaction. The potential antibacterial activity against gram positive (S. aureus) and gram negative (E. coli) bacteria were investigated. It was shown that the antibacterial properties were independent of the NP morphology as well as of the texture of the synthesis... 

    Microstructural characterization and antibacterial activity of carbon nanotube decorated with Cu nanoparticles synthesized by a novel solvothermal method

    , Article Ceramics International ; Volume 47, Issue 18 , 2021 , Pages 25729-25737 ; 02728842 (ISSN) Cao, Y ; Moniri Javadhesari, S ; Mohammadnejad, S ; khodadustan, E ; Raise, A ; Akbarpour, M. R ; Sharif University of Technology
    Elsevier Ltd  2021
    In this research, carbon nanotube decorated with Cu nanoparticles (CNT/Cu) was synthesized by a new solvothermal process. Solvothermal treatment of CuSO4 and NaOH was completed in ethanol containing ultrasonically dispersed CNTs at 160 °C for 3 h. In the solvothermal process, Cu nanoparticles were heterogeneously deposited on the surface of COOH-functionalized CNTs through the reduction of the Cu+2 ions. Cu nanoparticles with the size of ≈8 nm on CNTs (and some in the solution) and strong bonding between Cu and CNT were obtained by the used process. Microstructural characterization revealed that the solvothermal method is an appropriate method for producing homogenous CNT/Cu nanostructure.... 

    Carrageenan-Based functional films integrated with cuo-doped titanium nanotubes for active food-packaging applications

    , Article ACS Sustainable Chemistry and Engineering ; Volume 9, Issue 28 , 2021 , Pages 9300-9307 ; 21680485 (ISSN) Ezati, P ; Riahi, Z ; Rhim, J. W ; Sharif University of Technology
    American Chemical Society  2021
    A titanium dioxide nanotube (TNT) and CuO-doped TNT (TNT-CuO) were synthesized using a hydrothermal method and incorporated into carrageenan-based films. The SEM results confirmed the formation of uniform nanocomposite films. The addition of nanoparticles imparted UV-blocking properties to the carrageenan film and increased the mechanical strength, surface hydrophobicity, and water vapor barrier properties. The modified TiO2 (TNT and TNT-CuO)-incorporated carrageenan films showed significantly higher antibacterial activity than the TiO2-added film under visible light. Bananas packaged with the neat carrageenan and TiO2-added films were degraded considerably after 12 days of storage at 20 °C.... 

    Mixed oxide nanotubes in nanomedicine: A dead-end or a bridge to the future?

    , Article Ceramics International ; Volume 47, Issue 3 , 2021 , Pages 2917-2948 ; 02728842 (ISSN) Sarraf, M ; Nasiri Tabrizi, B ; Yeong, C. H ; Madaah Hosseini, H. R ; Saber-Samandari, S ; Basirun, W. J ; Tsuzuki, T ; Sharif University of Technology
    Elsevier Ltd  2021
    Nanomedicine has seen a significant rise in the development of new research tools and clinically functional devices. In this regard, significant advances and new commercial applications are expected in the pharmaceutical and orthopedic industries. For advanced orthopedic implant technologies, appropriate nanoscale surface modifications are highly effective strategies and are widely studied in the literature for improving implant performance. It is well-established that implants with nanotubular surfaces show a drastic improvement in new bone creation and gene expression compared to implants without nanotopography. Nevertheless, the scientific and clinical understanding of mixed oxide... 

    Evaluation of antibacterial behavior of in situ grown CuO-GO nanocomposites

    , Article Materials Today Communications ; Volume 28 , 2021 ; 23524928 (ISSN) Ahmadi, R ; Fattahi Nafchi Fatahi, R ; Sangpour, P ; Bagheri, M ; Rahimi, T ; Sharif University of Technology
    Elsevier Ltd  2021
    The growth of harmful microorganisms is a severe threat to human life. Nowadays, it is necessary to prepare antimicrobials materials with high biocompatibility properties. Hence, the use of nanomaterials and their nanocomposites has been proposed as a suitable way to obtain safe and potent antibacterial materials. Recently, several studies have been conducted on the antibacterial properties of metal oxide and graphene oxide (GO) nanomaterials individually. This study investigated the synergistic effect of GO and copper oxide (CuO) as a nanocomposite. CuO-GO nanocomposite containing 5%, 15%, 25%, 50%, and 75% of GO were synthesized to study antibacterial properties. X-ray diffraction (XRD)... 

    Investigation of synergistic effect of nano sized Ag/TiO2 particles on antibacterial, physical and mechanical properties of UV-curable clear coatings by experimental design

    , Article Progress in Organic Coatings ; Vol. 77, issue. 2 , February , 2014 , pp. 502-511 ; ISSN: 03009440 Labbani-Motlagh, A ; Bastani, S ; Hashemi, M. M ; Sharif University of Technology
    The synergistic effect of nano titanium dioxide (10 and 30 nm) and nano silver (10 nm) as antibacterial agents were investigated on UV curable clear coating. Antibacterial and physical-mechanical properties of coating were optimized using experimental design in response surface method. Twenty different samples of nano Ag and nano TiO2 were prepared in this method. Antibacterial properties on Gram-negative bacteria (Escherichia coli) were investigated. The results revealed that using equal amounts of two sizes of nano TiO2 promote the antibacterial activity of nano Ag. So, the coating shows strong activity against E. coli. Physical-mechanical properties such as surface hardness, abrasion... 

    Investigation of mechanical properties, antibacterial features, and water vapor permeability of polyvinyl alcohol thin films reinforced by glutaraldehyde and multiwalled carbon nanotube

    , Article Polymer Composites ; Vol. 35,Issue. 9 , 2014 , pp. 1736-1743 ; ISSN: 1548-0569 Mohammad Mahdi Dadfar, S ; Kavoosi, G ; Mohammad Ali Dadfar, S ; Sharif University of Technology
    Polyvinyl alcohol (PVA) thin films were reinforced by glutaraldehyde and multiwalled carbon nanotubes (MWCNTs) and then mechanical, water solubility, water swelling, water uptake, water vapor permeability, and antibacterial properties of the films were examined. Cross-linking by glutaraldehyde or incorporation of MWCNT caused a significant increase in tensile strength, decrease in elongation at break, and increase in Young's modulus of the PVA films, while MWCNTs were more effective rather than that of glutaraldehyde. Cross-linking by glutaraldehyde or incorporation of MWCNT caused a significant decrease in water solubility, water swelling and water uptake, with a similar manner.... 

    Dextran-graft-poly(hydroxyethyl methacrylate) gels: A new biosorbent for fluoride removal of water

    , Article Designed Monomers and Polymers ; Volume 16, Issue 2 , 2013 , Pages 127-136 ; 1385772X (ISSN) Ahmari, A ; Mousavi, S. A ; Amini Fazl, A ; Amini Fazl, M. S ; Ahmari, R ; Sharif University of Technology
    Synthesis of dextran-graft-poly(hydroxyethyl methacrylate) gels as a new fluoride biosorbent was considered in this work. For this propose, the Taguchi experimental design method was used for optimizing the synthetic conditions of the gels to reach high level of fluoride absorbency. The effects of three main parameters including concentrations of monomer (hydroxyethyl methacrylate), crosslinking agent (ethylene glycol dimethacrylate), and initiator (ammonium persulfate) on the final properties of the prepared gels were investigated. The proposed mechanism for grafting and chemically crosslinking reactions was proved with equilibrium water absorption, Fourier-transformed infrared, scanning... 

    Investigation of the antibacterial and photocatalytic properties of the zeolitic nanosized AgBr/TiO 2 composites

    , Article Materials Science in Semiconductor Processing ; Volume 15, Issue 1 , February , 2012 , Pages 73-79 ; 13698001 (ISSN) Padervand, M ; Elahifard, M. R ; Vatan Meidanshahi, R ; Ghasemi, S ; Haghighi, S ; Gholami, M. R ; Sharif University of Technology
    Zeolite-based Ag/AgBr and Ag/AgBr/TiO 2 photocatalysts were prepared by sol-gel and deposition methods and were characterized. Their photocatalytic activities were evaluated by inactivation of Escherichia (E.) coli and the photodegradation of Acid Blue 92 and potassium permanganate. The composites containing Ag/AgBr showed the antibacterial activity in the dark by releasing Ag ions into the medium. The results for inactivation of E. coli indicated that Ag/AgBr/TiO 2 modified photocatalyst had better antibacterial activity than Ag/AgBr/zeolite, while zeolite and TiO 2/zeolite did not show any antibacterial activity under visible light and dark conditions. Photodecolarization rate was affected... 

    CuO/Cu(OH)2 hierarchical nanostructures as bactericidal photocatalysts

    , Article Journal of Materials Chemistry ; Volume 21, Issue 26 , May , 2011 , Pages 9634-9640 ; 09599428 (ISSN) Akhavan, O ; Azimirad, R ; Safa, S ; Hasani, E ; Sharif University of Technology
    Various morphologies of CuO/Cu(OH)2 nanostructures with different adsorbed -OH contents were synthesized on an acid-treated Cu foil through variation of NaOH concentration from 0 to 50 mM with an in situ oxidation method. X-ray diffractometry and X-ray photoelectron spectroscopy (XPS) indicated formation of CuO on the Cu(OH)2 crystalline phase at a growth temperature of 60°C for 20 h. Antibacterial activity of the nanostructures against Escherichia coli bacteria was studied in the dark and under light irradiation. The nanostructures grown at a NaOH concentration of 30 mM showed the highest surface area and the strongest antibacterial activity among the samples. After elimination of the... 

    Influence of plasma sputtering treatment on natural dyeing and antibacterial activity of wool fabrics

    , Article Progress in Organic Coatings ; Volume 70, Issue 4 , 2011 , Pages 388-393 ; 03009440 (ISSN) Ghoranneviss, M ; Shahidi, S ; Anvari, A ; Motaghi, Z ; Wiener, J ; Šlamborová, I ; Sharif University of Technology
    In this paper, the effect of plasma sputtering treatment on the natural dyeing properties of wool and the possibility of substituting it for mordant treatment have been studied. We used madder and weld as natural dyes and copper sulfate (CuSO4) as a metal mordant. We also used, copper as the electrode material, in a DC magnetron plasma sputtering device. The color strength of samples was analyzed using a Reflective Spectrophotometer and washing and light fastnesses were investigated according to I.S.O. standard recommendations. The results show that, the color strength and fastness of dyed wool samples have been improved after plasma treatment. The antibacterial counting test was also used... 

    Silver nanoparticles within vertically aligned multi-wall carbon nanotubes with open tips for antibacterial purposes

    , Article Journal of Materials Chemistry ; Volume 21, Issue 2 , Oct , 2011 , Pages 387-393 ; 09599428 (ISSN) Akhavan, O ; Abdolahad, M ; Abdi, Y ; Mohajerzadeh, S ; Sharif University of Technology
    Vertically aligned multi-wall carbon nanotube (CNT) arrays were fabricated in tip-growth mode on Ni/Si substrates using plasma enhanced chemical vapor deposition. In a purification process including hydrogenation and acid washing of the Ni/CNTs, the oxygen-containing functional groups were substantially reduced and a wide hollow core at the tip of the CNTs was formed by removing the Ni seeds. Sol-gel silver nanoparticles were deposited on the surface of the unpurified Ni/CNTs, while they could also be embedded within the hollow core of the Ni-removed CNTs. The persistency of the silver ions in the Ni-removed Ag-CNTs in comparison to the release of the silver ions from the Ag-Ni/CNTs in a... 

    Visible light photo-induced antibacterial activity of CNT-doped TiO 2 thin films with various CNT contents

    , Article Journal of Materials Chemistry ; Volume 20, Issue 35 , Jun , 2010 , Pages 7386-7392 ; 09599428 (ISSN) Akhavan, O ; Azimirad, R ; Safa, S ; Larijani, M. M ; Sharif University of Technology
    Carbon nanotube (CNT)-doped TiO2 thin films with various CNT contents were synthesized by sol-gel method for visible light photoinactivation of Escherichia coli bacteria. Post annealing of the CNT-doped TiO2 thin films at 450 °C resulted in anatase TiO2 and formation of Ti-C and Ti-O-C carbonaceous bonds in the film. By increasing the CNT content, the thin films could further inactivate the bacteria in the dark. Meanwhile, as the CNT content increased from zero to 40 wt% the effective optical band gap energy of the CNT-doped TiO2 thin films annealed at 450 °C decreased from 3.2-3.3 to less than ∼2.8 eV providing light absorption in the visible region. Concerning this, visible light...