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High-gravity-assisted green synthesis of palladium nanoparticles: the flowering of nanomedicine
, Article Nanomedicine: Nanotechnology, Biology, and Medicine ; Volume 30 , November , 2020 ; Rabiee, N ; Bagherzadeh, M ; Ghadiri, A. M ; Fatahi, Y ; Dinarvand, R ; Webster, T. J ; Sharif University of Technology
Elsevier Inc
2020
Abstract
This study investigated the synthesis of Pd nanoparticles (NPs) using a high-gravity technique mediated by Salvia hispanica leaf extracts. Biological assays confirmed their antibacterial activity against gram positive (S. aureus) and gram negative (E. coli) bacteria with significant antioxidant activity in comparison with the standards as well as low cellular toxicity on PC12 and HEK293 cell lines. To the best of our knowledge, this study can be considered as the first investigation of Pd-NPs synthesized by Salvia hispanica leaf extracts assisted by a high-gravity technique. In addition, the mentioned green synthesis procedure led to the formation of nanoparticles with considerable...
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) ; Rabiee, N ; Bagherzadeh, M ; Ghadiri, A.M ; Fatahi, Y ; Dinarvand, R ; Webster, T. J ; Sharif University of Technology
Elsevier Inc
2021
Abstract
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...
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...
Production of l-asparaginase from Escherichia coli ATCC 11303: Optimization by response surface methodology
, Article Food and Bioproducts Processing ; Volume 89, Issue 4 , Oct , 2011 , Pages 315-321 ; 09603085 (ISSN) ; Alemzadeh, I ; Maghsodi, V ; Sharif University of Technology
2011
Abstract
This paper discusses the studies carried out for the optimal production of enzyme l-asparaginase (l-asparagine amidohydrolase, EC 3.5.1.1) from Escherichia coli (ATCC 11303). It was found that inoculum age of 18 h and inoculum size of 10% were the most favorable operating conditions for enzyme production. Lactose, yeast extract and KH 2PO 4 were found to be the best carbon, nitrogen and ion sources, respectively. Statistical method was used to survey how various medium conditions affect the enzyme production. By response surface methodology, the values of lactose, tryptone, yeast extract, KH 2PO 4 and l-asparagine concentration were investigated to obtain the maximum enzyme activity. The...
Substrate oscillations boost recombinant protein release from Escherichia coli
, Article Bioprocess and Biosystems Engineering ; Volume 37, Issue 5 , May , 2014 , Pages 881-890 ; ISSN: 16157591 ; Herwig, C ; Sharif University of Technology
Abstract
Intracellular production of recombinant proteins in prokaryotes necessitates subsequent disruption of cells for protein recovery. Since the cell disruption and subsequent purification steps largely contribute to the total production cost, scalable tools for protein release into the extracellular space is of utmost importance. Although there are several ways for enhancing protein release, changing culture conditions is rather a simple and scalable approach compared to, for example, molecular cell design. This contribution aimed at quantitatively studying process technological means to boost protein release of a periplasmatic recombinant protein (alkaline phosphatase) from E. coli....
Effects of temperature shifts and oscillations on recombinant protein production expressed in Escherichia coli
, Article Bioprocess and Biosystems Engineering ; Volume 36, Issue 11 , 2013 , Pages 1571-1577 ; 16157591 (ISSN) ; Herwig, C ; Sharif University of Technology
2013
Abstract
Escherichia coli is widely used host for the intracellular expression of many proteins. However, in some cases also secretion of protein from periplasm was observed. Improvement of both intracellular and extracellular production of recombinant protein in E. coli is an attractive goal in order to reduce production cost and increase process efficiency and economics. Since heat shock proteins in E. coli were reported to be helpful for protein refolding and hindering aggregation, in this work different types of single and periodic heat shocks were tested on lab scale to enhance intracellular and extracellular protein production. A single heat shock prior to induction and different oscillatory...
Antibacterial and antifungal activity of methanolic extracts of Salix alba L. against various disease causing pathogens
, Article Brazilian journal of biology = Revista brasleira de biologia ; Volume 83 , 2021 , Pages e243332- ; 16784375 (ISSN) ; Farooq, F ; Ibrahim, M ; Abbas, H. A. B ; Jawwad, H ; Zehra, S. S ; Ahmad, H. M ; Sarwer, A ; Malik, K ; Nawaz, K ; Sharif University of Technology
NLM (Medline)
2021
Abstract
The present study was aimed to manifest the antibacterial and antifungal activity of methanolic extracts of Salix alba L. against seven Gram-positive and Gram-negative bacterial pathogens e.g. Streptococcus pyogenes, Staphylococcus aureus (1), S. aureus (2), Shigella sonnei, Escherichia coli (1), E. coli (2) and Neisseria gonorrhoeae and three fungal isolates from the air such as Aspergillus terreus, A. ornatus, and Rhizopus stolonifer. Two different serotypes of S. aureus and E. coli were used. The agar well-diffusion method results showed the dose-dependent response of plant extracts against bacterial and fungal strains while some organisms were found resistant e.g. E. coli (1), S. sonnei,...
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...
Functional properties of biodegradable corn starch nanocomposites for food packaging applications
, Article Materials and Design ; Volume 50 , 2013 , Pages 954-961 ; 02613069 (ISSN) ; Alemzadeh, I ; Vossoughi, M ; Sharif University of Technology
Elsevier Ltd
2013
Abstract
In this research, response surface methodology (RSM) was applied to study the effects of Na-Montmorillonite (Na-MMT) and glycerol on some functional properties of corn starch films. Films were prepared by casting method according to central composite design (CCD). Originally image processing technique was used in order to estimate transparency of the films. It was found that Na-MMT absorbed UV light from 216 to 266. nm. No antimicrobial activities were observed against Escherichia coli and Staphylococcus aureus. Contact angle analysis revealed hydrophilicity of starch films decreased utilizing nanoparticles and increased with plasticizer content. Increase in glycerol content decreased...
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)...
Antibacterial properties of nanoporous graphene oxide/cobalt metal organic framework
, Article Materials Science and Engineering C ; Volume 104 , 2019 ; 09284931 (ISSN) ; 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
Abstract
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...
Hyperthermia response of PEGylated magnetic graphene nanocomposites for heating applications and accelerate antibacterial activity using magnetic fluid hyperthermia
, Article Applied Physics A: Materials Science and Processing ; Volume 126, Issue 4 , 2020 ; Shih, P. J ; Soufi Zomorod, M ; Heravi, P ; Ahadian, M. M ; Hatami, N ; Sharif University of Technology
Springer
2020
Abstract
In this research work, graphene/cobalt nanocomposites are functionalized with polyethylene glycol (PEG) to be a platform for theranostics application and antibacterial activity. The non-covalent functionalization of PEG on the surfaces of nanocomposites improved their stability and diminished their cytotoxicity. The PEGylated nanocomposites are demonstrated to allow simultaneous administration of two cancer therapy methods such as magnetic fluids hyperthermia (MFH) which is carried out by converting magnetic energy into heat through ferromagnetic cobalt nanoparticles and heat generation through near-infrared optical absorption by the reduced graphene oxide. A concise simulation is carried...
DNA and RNA extractions from eukaryotic and prokaryotic cells by graphene nanoplatelets
, Article RSC Advances ; Vol. 4, issue. 105 , 2014 , p. 60720-60728 ; Akhavan, O ; Shamsara, M ; Valimehr, S ; Rahighi, R ; Sharif University of Technology
Abstract
Graphene nanoplatelets with lateral dimensions of ∼50-200 nm and thicknesses <2 nm were utilized for the extraction of nucleic acids (NAs) from eukaryotic and prokaryotic cells. The graphene nanoplatelets (both chemically exfoliated graphene oxide nanoplatelets and hydrazine-reduced graphene oxide nanoplatelets) successfully extracted plasmid DNA (pDNA) from Escherichia coli bacteria, comparable to a conventional phenol-chloroform (PC) method. Furthermore, it was found that the yield of graphene nanoplatelets in genomic DNA (gDNA) and RNA extractions from embryonic stem cells (ESCs) was also comparable to the yield of the conventional methods. The effects of the graphene nanoplatelets on...
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+,...
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...
Preparation, physicochemical properties, in vitro evaluation and release behavior of cephalexin-loaded niosomes
, Article International Journal of Pharmaceutics ; Volume 569 , 2019 ; 03785173 (ISSN) ; Akbarzadeh, I ; Tavakkoli Yaraki, M ; Lajevardi, A ; Fatemizadeh, M ; Heidarpoor Saremi, L ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In this study, optimized cephalexin-loaded niosomal formulations based on span 60 and tween 60 were prepared as a promising drug carrier system. The niosomal formulations were characterized using a series of techniques such as scanning electron microscopy, Fourier transformed infrared spectroscopy, dynamic light scattering, and zeta potential measurement. The size and drug encapsulation efficiency are determined by the type and composition of surfactant. The developed niosomal formulations showed great storage stability up to 30 days with low change in size and drug entrapment during the storage, making them potential candidates for real applications. Moreover, the prepared niosomes showed...
Denoising of genetic switches based on Parrondo's paradox
, Article Physica A: Statistical Mechanics and its Applications ; Volume 493 , 2018 , Pages 410-420 ; 03784371 (ISSN) ; Fatemizadeh, E ; Pezeshk, H ; Sadeghi, M ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Random decision making in genetic switches can be modeled as tossing a biased coin. In other word, each genetic switch can be considered as a game in which the reactive elements compete with each other to increase their molecular concentrations. The existence of a very small number of reactive element molecules has caused the neglect of effects of noise to be inevitable. Noise can lead to undesirable cell fate in cellular differentiation processes. In this paper, we study the robustness to noise in genetic switches by considering another switch to have a new gene regulatory network (GRN) in which both switches have been affected by the same noise and for this purpose, we will use Parrondo's...
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 of operating parameters for efficient photocatalytic inactivation of Escherichia coli based on a statistical design of experiments
, Article Water Science and Technology ; Volume 71, Issue 6 , 2015 , Pages 823-831 ; 02731223 (ISSN) ; Alemzadeh, I ; Delparish, A ; Karimi Estahbanati, M. R ; Soleimani, M ; Jangjou, Y ; Vosoughi, A ; Sharif University of Technology
IWA Publishing
2015
Abstract
In this work, the individual and interaction effects of three key operating parameters of the photocatalytic disinfection process were evaluated and optimized using response surface methodology (RSM) for the first time. The chosen operating parameters were: reaction temperature, initial pH of the reaction mixture and TiO2 P-25 photocatalyst loading. Escherichia coli concentration, after 90 minutes irradiation of UV-A light, was selected as the response. Twenty sets of photocatalytic disinfection experiments were conducted by adjusting operating parameters at five levels using the central composite design. Based on the experimental data, a semi-empirical expression was established and applied...
Ternary composite of TiO2 nanotubes/Ti plates modified by g-C3N4 and SnO2 with enhanced photocatalytic activity for enhancing antibacterial and photocatalytic activity
, Article Journal of Photochemistry and Photobiology B: Biology ; Volume 178 , 2018 , Pages 124-132 ; 10111344 (ISSN) ; Mohaghegh, N ; Abedini, A ; Sharif University of Technology
Elsevier B.V
2018
Abstract
A series of g-C3N4-SnO2/TiO2 nanotubes/Ti plates were fabricated via simple dipping of TiO2 nanotubes/Ti in a solution containing SnCl2 and g-C3N4 nanosheets and finally annealing of the plates. Synthesized plates were characterized by various techniques. The SEM analysis revealed that the g-C3N4-SnO2 nanosheets with high physical stability have been successfully deposited onto the surface of TiO2 nanotubes/Ti plate. Photocatalytic activity was investigated using two probe chemical reactions: oxidative decomposition of acetic acid and oxidation of 2-propanol under irradiation. Antibacterial activities for Escherichia coli (E. coli) bacteria were also investigated in dark and under UV/Vis...