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Design and application of (Fe3O4)-GOTfOH based AgNPs doped starch/PEG-poly (acrylic acid) nanocomposite as the magnetic nanocatalyst and the wound dress
, Article Journal of Molecular Structure ; Volume 1214 , 2020 ; Meskini, M ; Rami, M. R ; Sharif University of Technology
Elsevier B.V
2020
Abstract
As a novel, recyclable nanocatalyst, (Fe3O4)-GOTfOH based Ag nanoparticles doped Starch/PEG-poly (acrylic acid) nanocomposite (Fe3O4@GOTfOH/Ag/St-PEG-AcA) was applied for one-pot synthesis of 2,4,6-triarylpyridine derivatives under water solvent conditions. The prepared nanocomposite was also evaluated in terms of biocompatibility for wound healing. Fe3O4@GOTfOH/Ag/St-PEG-AcA could be easily removed from the mixture of the reaction by an external magnet and recycled without a considerable decrease of activity even after 10 runs. The new nanocatalyst offered better efficiencies than other commercially available sulfonic acid catalysts. In terms of the bioactivity of nanocatalyst, good...
Optimization and characterization of tannic acid loaded niosomes for enhanced antibacterial and anti-biofilm activities
, Article Advanced Powder Technology ; 2020 ; Akbarzadeh, I ; Nourouzian, D ; Mirzaie, A ; Bakhshandeh, H ; Sharif University of Technology
Elsevier B.V
2020
Abstract
The purpose of this study was to prepare and characterize an optimized system of tannic acid-loaded niosomes as a potential carrier for antibacterial and anti-biofilm delivery. The niosomal formulation was optimized using response surface methodology (RSM). The effects of the molar ratio of surfactant to cholesterol, drug concentration, and molar ratio of Span 60 to Tween 60 on particle size and drug entrapment efficiency of the niosomal nanocarrier were studied. The optimized nanoparticles were characterized in terms of the morphology, in vitro release profile, and antibacterial properties. Moreover, Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC)...
Biocompatibility, osseointegration, antibacterial and mechanical properties of nanocrystalline Ti-Cu alloy as a new orthopedic material
, Article Colloids and Surfaces B: Biointerfaces ; Volume 189 , May , 2020 ; Alipour, S ; Akbarpour, M. R ; Sharif University of Technology
Elsevier B.V
2020
Abstract
The demands for high-performance biomaterials are driving the development of new metallic alloys with improved mechanical and biological responses. In this study, a nanocrystalline Ti-Cu intermetallic alloy was prepared by a powder metallurgy route, and its application as an orthopedic material was evaluated by the microstructural, mechanical, corrosion, antibacterial, cytotoxicity and osseointegration examinations. Microstructural characterization revealed the formation of TiCu and Ti2Cu3 as major phases with 23 nm grain size in the structure of the alloy. The synthesized alloy exhibited ultra-high hardness of 10 GPa, acceptable toughness of 8.14 MPam1/2, a ∼98 % anti-bacterial rate against...
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 ; Bagherzadeh, M ; Kiani, M ; Ghadiri, A. M ; Sharif University of Technology
Elsevier B.V
2020
Abstract
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...
Highly efficient of molybdenum trioxide-cadmium titanate nanocomposites for ultraviolet light photocatalytic and antimicrobial application: Influence of reactive oxygen species
, Article Journal of Photochemistry and Photobiology B: Biology ; Volume 191 , 2019 , Pages 75-82 ; 10111344 (ISSN) ; Hosseini, M ; Fakhri, A ; Salari Rad, S ; Hadadi, T ; Nobakht, N ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In the present work we report the enhanced UV light photocatalytic performance of cadmium titanate photocatalyst by MoO 3 for Drug pollutant degradation. The nano photocatalyst sample was synthesized employing the Pechini-ultrasonic-hydrothermal route. Therefore, the nano photocatalyst were characterized by various analytical devices. The wide scan X-ray photoelectron spectral study confirmed the MoO 3 in the CdTiO 3 matrix. The crystallite size calculated with the Debye-Scherrer equation (55.4, 57.0, 61.2 and 63.1 nm for pure CdTiO 3 , MoCdTi-0, MoCdTi-1, and MoCdTi-2 nanocomposites, respectively). SEM micrographs revealed nanowire morphology indicated the crystalline nature of the sample....
An innovative, highly stable Ag/ZIF-67@GO nanocomposite with exceptional peroxymonosulfate (PMS) activation efficacy, for the destruction of chemical and microbiological contaminants under visible light
, Article Journal of Hazardous Materials ; Volume 413 , 2021 ; 03043894 (ISSN) ; Giannakis, S ; Moussavi, G ; Bensimon, M ; Gholami, M. R ; Pulgarin, C ; Sharif University of Technology
Elsevier B.V
2021
Abstract
In this work, Ag nanoparticles were loaded on ZIF-67 covered by graphene oxide (Ag/ZIF-67@GO), and its catalytic performance was studied for the heterogeneous activation of peroxymonosulfate (PMS) under visible-light. The catalyst surface morphology and structure were analyzed by FT-IR, XRD, XPS, DRS, FE-SEM, EDX, TEM, BET, ICP-AES and TGA analysis. The efficacy of PMS activation by the Ag/ZIF-67@GO under visible light was assessed by phenol degradation and E. coli inactivation. Phenol was completely degraded within 30 min by HO•, SO4•− and O2•− generated through the photocatalytic PMS activation. In addition, total E. coli inactivation was attained in 15 min that confirmed the highly...
Alginate-based multifunctional films incorporated with sulfur quantum dots for active packaging applications
, Article Colloids and Surfaces B: Biointerfaces ; Volume 215 , 2022 ; 09277765 (ISSN) ; Priyadarshi, R ; Rhim, J. W ; Lotfali, E ; Bagheri, R ; Pircheraghi, G ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Sulfur quantum dots (SQDs) were fabricated using a facile hydrothermal method and used for the preparation of functional food packaging film and compared the properties with other sulfur-based fillers like elemental sulfur (ES) and sulfur nanoparticles (SNP). The SQDs have an average size of 5.3 nm and were very stable in aqueous suspension. Unlike other sulfur-based fillers, the SQD showed high antioxidant, antibacterial and antifungal activity, but no cytotoxicity was found for L929 mouse fibroblasts even after long-term exposure of 48 h. When sulfur-based fillers were added to the alginate film, SQD was more evenly dispersed in the polymer matrix than SNP and ES. The addition of SQD to...
Amoxicillin-loaded multilayer pullulan-based nanofibers maintain long-term antibacterial properties with tunable release profile for topical skin delivery applications
, Article International Journal of Biological Macromolecules ; Volume 215 , 2022 , Pages 413-423 ; 01418130 (ISSN) ; Asgari, S ; Guerra, P. R ; Chamorro, C. I ; Ilchenco, O ; Piqueras, S ; Fossum, M ; Boisen, A ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Unique physiochemical and biological properties of nanofibers along with the choice of a wide variety of materials for both fabrication and tunable release patterns make nanofibers an ideal option for drug delivery. Loading antibacterial agents into nanofibers has attracted great deal of attention. Whilst there are several studies focusing on applying new generations of antibacterial materials, antibiotics are still the gold standard in clinical applications. Therefore, we aimed at introducing antibiotic-loaded nanofiber substrates with potential for topical skin delivery applications, reduced consumption of antibiotics and increased storage time. We applied Amoxicillin (AMX) as a model drug...
Carboxymethyl cellulose-based functional film integrated with chitosan-based carbon quantum dots for active food packaging applications
, Article Progress in Organic Coatings ; Volume 166 , 2022 ; 03009440 (ISSN) ; Rhim, J. W ; Bagheri, R ; Pircheraghi, G ; Lotfali, E ; Sharif University of Technology
Elsevier B.V
2022
Abstract
A chitosan-based carbon quantum dots (CQDs) with multifunctional properties were synthesized using a hydrothermal process. The CQDs were spherical with an average size of 7.8 ± 2.4 nm. The CQD showed strong antioxidant activity, potent antibacterial activity against E. coli and L. monocytogenes, and antifungal activity against A. niger and P. chrysogenum. In addition, the prepared CQD showed negligible cytotoxicity against L929 cells even at a concentration of 500 μg/mL. Carboxymethyl cellulose (CMC)-based functional films were fabricated by adding various amounts of CQD. The CQDs were evenly dispersed in the polymer matrix to form a highly transparent UV-blocking film. The addition of CQD...
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) ; Azimirad, R ; Amini, A ; Akhavan, O ; Sharif University of Technology
Elsevier
2015
Abstract
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...
Optimized doxycycline-loaded niosomal formulation for treatment of infection-associated prostate cancer: An in-vitro investigation
, Article Journal of Drug Delivery Science and Technology ; Volume 57 , 2020 ; Tavakkoli Yaraki, M ; Bourbour, M ; Noorbazargan, H ; Lajevardi, A ; Sadat Shilsar, S. M ; Heidari, F ; Mousavian, S. M ; Sharif University of Technology
Editions de Sante
2020
Abstract
Developing drug delivery systems with both antibacterial and anti-cancer effects is of importance in the treatment process of infection-associated cancers, especially prostate cancer. In this study, Span 60, Tween 60, and cholesterol were used to formulate doxycycline-loaded niosomes as a promising drug carrier system as either antibacterial or anticancer formulation. The formulation process was optimized by multi-objective response surface methodology (RSM), and then characterized. The developed niosomal formulation showed great storage stability for up to 2 weeks. In addition, they showed remarkable drug release in acidic solution (pH = 3) compared with physiological pH (7.4). The in-vitro...
Biosynthesis of copper oxide nanoparticles with potential biomedical applications
, Article International Journal of Nanomedicine ; Volume 15 , 2020 , Pages 3983-3999 ; Bagherzadeh, M ; Kiani, M ; Ghadiri, A. M ; Etessamifar, F ; Jaberizadeh, A. H ; Shakeri, A ; Sharif University of Technology
Dove Medical Press Ltd
2020
Abstract
Introduction: In recent years, the use of cost-effective, multifunctional, environmentally friendly and simple prepared nanomaterials/nanoparticles have been emerged considerably. In this manner, different synthesizing methods were reported and optimized, but there is still lack of a comprehensive method with multifunctional properties. Materials and Methods: In this study, we aim to synthesis the copper oxide nanoparticles using Achillea millefolium leaf extracts for the first time. Catalytic activity was investigated by in situ azide alkyne cycloaddition click and also A3 coupling reaction, and optimized in terms of temperature, solvent, and time of the reaction. Furthermore, the...
Biodegradation of synthetic dye using partially purified and characterized laccase and its proposed mechanism
, Article International Journal of Environmental Science and Technology ; Volume 16, Issue 12 , 2019 , Pages 7805-7816 ; 17351472 (ISSN) ; Borghei, S. M ; Yaghmaei, S ; Sharif University of Technology
Center for Environmental and Energy Research and Studies
2019
Abstract
The supernatant obtained from the extracellular laccase produced by Phanerochaete chrysosporium was used as the enzyme source to conduct a partial purification, characterization and dye decolorization study. The partially purified enzyme was stable in the pH range of 3–5 and showed an optimum activity at pH 4.0, using guaiacol as a substrate. Laccase stability of pH was determined and discovered to retain 100% of its activity at a pH of 4.0 after 2 h. The maximum enzyme activity was obtained between 30 and 50 °C. The maximum velocity and Michaelis constant were calculated as 3.171 µM−1·min and 1628.23 µM, respectively. The enzyme was activated by Fe2+, Zn2+, Ca2+ and Cu2+, while Hg2+, Mn2+,...
Chaperones promote remarkable solubilization of salmonella enterica serovar enteritidis flagellin expressed in escherichia coli
, Article Protein and Peptide Letters ; Volume 27, Issue 3 , 2020 , Pages 210-218 ; Sadeghi, Z ; Tarahomjoo, S ; Yaghmaie, S ; Sharif University of Technology
Bentham Science Publishers
2020
Abstract
Background: Flagellin of Salmonella enterica serovar Enteritidis (SEF) stimulates immune responses to both itself and coapplied antigens. It is therefore used in vaccine development and immunotherapy. Removal of pathogenic S. enterica ser. Enteritidis from SEF production process is advantageous due to the process safety improvement. The protein solubility analysis using SDS-PAGE indicated that 53.49% of SEF expressed in Escherichia coli formed inclusion bodies. However, the protein recovery from inclusion bodies requires a complex process with a low yield. Objective: We thus aim to study possibility of enhancing SEF expression in E. coli in soluble form using chemical and molecular...
Wrapping bacteria by graphene nanosheets for isolation from environment, reactivation by sonication, and inactivation by near-infrared irradiation
, Article Journal of Physical Chemistry B ; Volume 115, Issue 19 , 2011 , Pages 6279-6288 ; 15206106 (ISSN) ; Ghaderi, E ; Esfandiar, A ; Sharif University of Technology
American Chemical Society
2011
Abstract
Bioactivity of Escherichia coli bacteria (as a simple model for microorganisms) and interaction of them with the environment were controlled by their capturing within aggregated graphene nanosheets. The oxygen-containing functional groups of chemically exfoliated single-layer graphene oxide nanosheets were reduced by melatonin as a biocompatible antioxidant. While each one of the graphene (oxide) suspension and melatonin solution did not separately show any considerable inactivation effects on the bacteria, aggregation of the sheets in the melatonin-bacterial suspension resulted in trapping the bacteria within the aggregated sheets, i.e., a kind of inactivation. The bacteria trapped within...
High antimicrobial activity and low human cell cytotoxicity of core-shell magnetic nanoparticles functionalized with an Antimicrobial Peptide
, Article ACS Applied Materials and Interfaces ; Volume 8, Issue 18 , 2016 , Pages 11366-11378 ; 19448244 (ISSN) ; Rai, A ; Pinto, S ; Evangelista, M ; Cardoso, R. M. S ; Paulo, C ; Carvalheiro, T ; Paiva, A ; Imani, M ; Simchi, A ; Durães, L ; Portugal, A ; Ferreira, L ; Sharif University of Technology
American Chemical Society
2016
Abstract
Superparamagnetic iron oxide nanoparticles (SPIONs) functionalized with antimicrobial agents are promising infection-targeted therapeutic platforms when coupled with external magnetic stimuli. These antimicrobial nanoparticles (NPs) may offer advantages in fighting intracellular pathogens as well as biomaterial-associated infections. This requires the development of NPs with high antimicrobial activity without interfering with the biology of mammalian cells. Here, we report the preparation of biocompatible antimicrobial SPION@gold core-shell NPs based on covalent immobilization of the antimicrobial peptide (AMP) cecropin melittin (CM) (the conjugate is named AMP-NP). The minimal inhibitory...
Smart chip for visual detection of bacteria using the electrochromic properties of polyaniline
, Article Analytical Chemistry ; Volume 91, Issue 23 , 2019 , Pages 14960-14966 ; 00032700 (ISSN) ; Farahmand Nejad, M. A ; Parolo, C ; Shahrokhian, S ; Merkoci, A ; Sharif University of Technology
American Chemical Society
2019
Abstract
Finding fast and reliable ways to detect pathogenic bacteria is crucial for addressing serious public health issues in clinical, environmental, and food settings. Here, we present a novel assay based on the conversion of an electrochemical signal into a more convenient optical readout for the visual detection of Escherichia coli. Electropolymerizing polyaniline (PANI) on an indium tin oxide screen-printed electrode (ITO SPE), we achieved not only the desired electrochromic behavior but also a convenient way to modify the electrode surface with antibodies (taking advantage of the many amine groups of PANI). Applying a constant potential to the PANI-modified ITO SPE induces a change in their...
Graphene/Cuo2nanoshuttles with controllable release of oxygen nanobubbles promoting interruption of bacterial respiration
, Article ACS Applied Materials and Interfaces ; Volume 12, Issue 32 , 2020 , Pages 35813-35825 ; Akhavan, O ; Madaah Hosseini, H. R ; Bakhshi, B ; Sharif University of Technology
American Chemical Society
2020
Abstract
An oxygen nanoshuttle based on a reduced graphene oxide/copper peroxide (rGO/CuO2) nanocomposite has been presented to deliver in situ oxygen nanobubbles (O2 NBs) for combating bacterial infections. In the presence of rGO, the solid source of oxygen (i.e., CuO2) was decomposed (in response to environmental conditions such as pH and temperature) into O2 NBs in a more controllable and long-lasting trend (from 60 to 144 h). In a neutral buffer, the O2 NBs experienced growth and collapse evolutions, creating a dynamic micro-nanoenvironment around the nanocomposite. In addition to effective battling against methicillin-resistant Staphylococcus aureus bacteria, the O2 NBs demonstrated superior...
Multifunctional 3D hierarchical bioactive green carbon-based nanocomposites
, Article ACS Sustainable Chemistry and Engineering ; Volume 9, Issue 26 , 2021 , Pages 8706-8720 ; 21680485 (ISSN) ; Bagherzadeh, M ; Ghadiri, A. M ; Kiani, M ; Fatahi, Y ; Tavakolizadeh, M ; Pourjavadi, A ; Jouyandeh, M ; Saeb, M. R ; Mozafari, M ; Shokouhimehr, M ; Varma, R. S ; Sharif University of Technology
American Chemical Society
2021
Abstract
Carbon-based nanocarriers such as multiwall carbon nanotubes (MWCNTs) and reduced graphene oxide (rGO) have shown promising delivery capabilities due to their low immunogenicity, superior internalization, and suitable cell penetration efficiency. Herein, a molecular engineering strategy is advanced for the one-pot synthesized rGO/MWCNT/Fe3O4/ZnO to enhance the stability of the nanocarrier in the biological matrix; green synthesized ZnO was responsible for water uptake and reduced cytotoxicity, while Fe3O4controlled the cellular internalization for gene delivery. Surface morphology of the ensuing nanocomposite was correlated with photocatalytic and gene delivery (CRISPR/Cas9) features. For...
Effect of graphene oxide nanosheets on visible light-assisted antibacterial activity of vertically-aligned copper oxide nanowire arrays
, Article Journal of Colloid and Interface Science ; Volume 521 , 2018 , Pages 119-131 ; 00219797 (ISSN) ; Ashari Astani, N ; Rahighi, R ; Tayyebi, A ; Tayebi, M ; Khezri, J ; Hashemi, E ; Rothlisberger, U ; Simchi, A ; Sharif University of Technology
Academic Press Inc
2018
Abstract
In the present work, the effect of graphene oxide (GO) nanosheets on the antibacterial activity of CuO nanowire arrays under visible light irradiation is shown. A combined thermal oxidation/electrophoretic deposition technique was employed to prepare three-dimensional networks of graphene oxide nanosheets hybridized with vertically aligned CuO nanowires. With the help of standard antibacterial assays and X-ray photoelectron spectroscopy, it is shown that the light-activated antibacterial response of the hybrid material against gram-negative Escherichia coli is significantly improved as the oxide functional groups of the GO nanosheets are reduced. In order to explore the physicochemical...