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Synthesis, morpho-structural properties, and catalytic performances of Pt-APA@Fe3O4/GO nanocomposite based on magnetical graphene in C–C coupling reactions and photoinactivation of E. coli
, Article Journal of Nanoparticle Research ; Volume 23, Issue 8 , 2021 ; 13880764 (ISSN) ; Sabounchei, S. J ; Yousefi, A ; Akhavan, O ; Sharif University of Technology
Springer Science and Business Media B.V
2021
Abstract
Herein, a novel Pt-APA composite (APA = pyridinium bromide salt) based on magnetic graphene oxide was synthesized and used as an effective catalyst. In this way, Fe3O4 nanoparticles are grown on graphene oxide (GO) nanosheets by a simple and practical method which creates a unique nanostructure (Fe3O4/GO) through dispersing uniformly among graphene nanosheets. The resulted Pt-APA composite was obtained via adding PtCl2 to an ethanol solution of Fe3O4/GO and α-keto stabilized pyridinium ylide in related conditions. The synthesized nanocomposite structure was identified using field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), energy dispersive...
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...
Evaluating the toxic effect of an antimicrobial agent on single bacterial cells with optical tweezers
, Article Biomedical Optics Express ; Volume 6, Issue 1 , 2015 , Pages 112-117 ; 21567085 (ISSN) ; Zhang, C ; Chen, J ; Reihani, S. N. S ; Chen, Z ; Sharif University of Technology
OSA - The Optical Society
2015
Abstract
We implement an optical tweezers technique to assess the effects of chemical agents on single bacterial cells. As a proof of principle, the viability of a trapped Escherichia coli bacterium is determined by monitoring its flagellar motility in the presence of varying concentrations of ethyl alcohol. We show that the “killing time” of the bacterium can be effectively identified from the correlation statistics of the positional time series recorded from the trap, while direct quantification from the time series or associated power spectra is intractable. Our results, which minimize the lethal effects of bacterial photodamage, are consistent with previous reports of ethanol toxicity that used...
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,...
Fabrication and characterization of scaffolds containing different amounts of allantoin for skin tissue engineering
, Article Scientific Reports ; Volume 11, Issue 1 , 2021 ; 20452322 (ISSN) ; Shamloo, A ; Bahadoran, M ; Moravvej, H ; Sharif University of Technology
Nature Research
2021
Abstract
Using the skin tissue engineering approach is a way to help the body to recover its lost skin in cases that the spontaneous healing process is either impossible or inadequate, such as severe wounds or burns. In the present study, chitosan/gelatin-based scaffolds containing 0.25, 0.5, 0.75, and 1% allantoin were created to improve the wounds’ healing process. EDC and NHS were used to cross-link the samples, which were further freeze-dried. Different in-vitro methods were utilized to characterize the specimens, including SEM imaging, PBS absorption and degradation tests, mechanical experiments, allantoin release profile assessment, antibacterial assay, and cell viability and adhesion tests....
Physicochemical and antibacterial properties of chitosan-polyvinylpyrrolidone films containing self-organized graphene oxide nanolayers
, Article Journal of Applied Polymer Science ; Volume 133, Issue 11 , 2016 ; 00218995 (ISSN) ; Ostadhossein, F ; Simchi, A ; Sharif University of Technology
John Wiley and Sons Inc
2016
Abstract
Chitosan films have a great potential to be used for wound dressing and food-packaging applications if their physicochemical properties including water vapor permeability, optical transparency, and hydrophilicity are tailored to practical demands. To address these points, in this study, chitosan (CS) was combined with polyvinylpyrrolidone (PVP) and graphene oxide (GO) nanosheets (with a thickness of ∼1 nm and lateral dimensions of few micrometers). Flexible and transparent films with a high antibacterial capacity were prepared by solvent casting methods. By controlling the evaporation rate of the utilized solvent (1 vol % acidic acid in deionized water), self-organization of GO in the...
Sustained release of CIP from TiO2-PVDF/starch nanocomposite mats with potential application in wound dressing
, Article Journal of Applied Polymer Science ; Volume 137, Issue 30 , 2020 ; Haddadi, S. A ; Amini, M ; Hasany, M ; Ramazani SaadatAbadi, A ; Sharif University of Technology
John Wiley and Sons Inc
2020
Abstract
Electrospinning is an economical and alluring method to fabricate wound dressing mats from a variety of natural and synthetic materials. In this study, polyvinylidene fluoride (PVDF) and starch composite mats containing ciprofloxacin (CIP) loaded on titanium dioxide nanoparticles (TiO2) were prepared. Fourier Transform Infrared spectra of CIP, synthesized TiO2 NPs, TiO2/CIP, and PVDF/starch composite mats are analyzed. Scanning electron microscopy images revealed that the fiber diameter of PVDF nanofibers thickens by increasing starch, which varies between 180 nm and 550 nm. Strain at break of PVDF, starch, PVDF/starch (2:1 w:w; P2S1), PVDF/starch (1:1 w:w; P1S1), PVDF/starch (1:2 w:w;...
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...
Streptomycin sulfate–loaded niosomes enables increased antimicrobial and anti-biofilm activities
, Article Frontiers in Bioengineering and Biotechnology ; Volume 9 , 2021 ; 22964185 (ISSN) ; Khayam, N ; Jamshidifar, E ; Pourseif, T ; Kianian, S ; Mirzaie, A ; Akbarzadeh, I ; Ren, Q ; Sharif University of Technology
Frontiers Media S.A
2021
Abstract
One of the antibiotics used to treat infections is streptomycin sulfate that inhibits both Gram-negative and -positive bacteria. Nanoparticles are suitable carriers for the direct delivery and release of drug agents to infected locations. Niosomes are one of the new drug delivery systems that have received much attention today due to their excellent biofilm penetration property and controlled release. In this study, niosomes containing streptomycin sulfate were prepared by using the thin layer hydration method and optimized based on the size, polydispersity index (PDI), and encapsulation efficiency (EE%) characteristics. It was found that the Span 60-to-Tween 60 ratio of 1.5 and the...
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...
Characterization of a microfluidic microbial fuel cell as a power generator based on a nickel electrode
, Article Biosensors and Bioelectronics ; Volume 79 , 2016 , Pages 327-333 ; 09565663 (ISSN) ; Yaghmaei, S ; Sharif University of Technology
Elsevier Ltd
2016
Abstract
This study reports the fabrication of a microfluidic microbial fuel cell (MFC) using nickel as a novel alternative for conventional electrodes and a non-phatogenic strain of Escherichia coli as the biocatalyst. The feasibility of a microfluidic MFC as an efficient power generator for production of bioelectricity from glucose and urea as organic substrates in human blood and urine for implantable medical devices (IMDs) was investigated. A maximum open circuit potential of 459mV was achieved for the batch-fed microfluidic MFC. During continuous mode operation, a maximum power density of 104Wm-3 was obtained with nutrient broth. For the glucose-fed microfluidic MFC, the maximum power density of...
Dynamical analysis of microfluidic microbial electrolysis cell via integrated experimental investigation and mathematical modeling
, Article Electrochimica Acta ; Volume 227 , 2017 , Pages 317-329 ; 00134686 (ISSN) ; Yaghmaei, S ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
The present study deals with the feasibility of a microfluidic microbial electrolysis cell (MEC) as an efficient biohydrogen generator for medical usage for the first time. The evaluation of nickel in microfluidic MEC as an alternative for conventional electrodes indicates successful performance in the improvement of bioenergy production. The maximum biohydrogen production rate and produced power density of 2.2 μW cm−2 and 1.4 μl H2 μl substrate−1 day−1 were obtained, respectively. It is considered a promising technology for medical usage due to the following factors: significant biohydrogen generation, low consumption of expensive materials, simple construction, and utilization of human...
Silver oxide nanoparticles-decorated tantala nanotubes for enhanced antibacterial activity and osseointegration of Ti6Al4V
, Article Materials and Design ; Volume 154 , 2018 , Pages 28-40 ; 02641275 (ISSN) ; Dabbagh, A ; Abdul Razak, B ; Nasiri Tabrizi, B ; Hosseini, H. R. M ; Saber Samandari, S ; Abu Kasim, N. H ; Yean, L. K ; Sukiman, N. L ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
A long-term antibacterial activity of implants without compromising their biocompatibility is highly desirable to minimize the biomaterial-associated infections. Although tantalum oxide nanotubes (Ta2O5 NTs) are promising coating materials for orthodontics and orthopedics applications, their insufficient antibacterial activity retains vulnerability to post-implantation infections. This study aimed to endow antibacterial characteristics to the Ta2O5 NTs-coated Ti6Al4V substrates by decoration of silver oxide nanoparticles (Ag2O NPs). The well-adherent Ta2O5 NTs were grown via anodization of a pure tantalum (Ta) layer coated by physical vapor deposition (PVD) on the Ti6Al4V substrates. The...
Antibacterial activity of ultra-small copper oxide (II) nanoparticles synthesized by mechanochemical processing against S. aureus and E. coli
, Article Materials Science and Engineering C ; Volume 105 , 2019 ; 09284931 (ISSN) ; Alipour, S ; Mohammadnejad, S ; Akbarpour, M. R ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
In this paper, ultra-small CuO nanoparticles (NPs) were synthesized through a mechanochemical method using two different Cu-containing precursors (i.e. CuSO4·5H2O and CuCl2·2H2O), and their structure and antibacterial activity were studied. From the microstructural studies, it was observed that CuO NPs have a spherical morphology and a narrow size distribution with 7 and 14 nm median particle sizes for CuCl2·2H2O and CuSO4.5H2O precursors, respectively. The CuCl2·2H2O derived nanoparticles showed more antibacterial activity than CuSO4.5H2O derived nanoparticles. The minimum inhibitory concentration (MIC) of the synthesized nanoparticles (derived from both precursors) against E. coli and...
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...
Gut-on-a-chip: Current progress and future opportunities
, Article Biomaterials ; Volume 255 , 2020 ; Nasiri, R ; Barros, N. R. D ; Tebon, P ; Thakor, J ; Goudie, M ; Shamloo, A ; Martin, M. G ; Khademhosseni, A ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Organ-on-a-chip technology tries to mimic the complexity of native tissues in vitro. Important progress has recently been made in using this technology to study the gut with and without microbiota. These in vitro models can serve as an alternative to animal models for studying physiology, pathology, and pharmacology. While these models have greater physiological relevance than two-dimensional (2D) cell systems in vitro, endocrine and immunological functions in gut-on-a-chip models are still poorly represented. Furthermore, the construction of complex models, in which different cell types and structures interact, remains a challenge. Generally, gut-on-a-chip models have the potential to...
Effects of SiC nanoparticles on synthesis and antimicrobial activity of TiCu nanocrystalline powder
, Article Ceramics International ; Volume 46, Issue 1 , January , 2020 , Pages 114-120 ; Alipour, S ; Akbarpour, M. R ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Effects of SiC nanoparticles addition on synthesis and antibacterial properties of TiCu nanocrystalline powder prepared through high energy mechanical milling were studied. The results showed that the synthesis of TiCu powder in the presence of the nanoparticles was accelerated and after mechanical alloying for 20 h, a TiCu/SiC nanocrystalline powder with the crystallite size <5 nm, and 3.3% lattice micro-strain obtained. Further milling resulted in fully amorphous TiCu intermetallic alloy with more uniform distribution of SiC nanoparticles. The antibacterial activity of the synthesized powders was investigated by disk diffusion test. The TiCu/SiC nanocomposites showed enhanced antibacterial...
Synergistic enhancement of photocatalytic antibacterial effects in high-strength aluminum/TiO2 nanoarchitectures
, Article Ceramics International ; Volume 46, Issue 15 , October , 2020 , Pages 24267-24280 ; Sarraf, M ; Dabbagh, A ; Nasiri Tabrizi, B ; Paria, S ; Banihashemian, S. M ; Bushroa, A. R ; Faraji, G ; Tsuzuki, T ; Madaah Hosseini, H. R ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Unlike gold and silver, aluminum shows a localized surface plasmon resonance (LSPR) over a wide spectral range from ultraviolet (UV) to the visible region. Herein, we demonstrate a new process to optically couple TiO2 nanotubes (NTs) with a high-strength aluminum substrate, to achieve a synergistic enhancement of photocatalytic antibacterial effects through controlled LSPR of aluminum. The high-strength aluminum substrate was produced by tubular channel angular pressing (TCAP). Their LSPR was tailored through the formation of superficial nano-concave arrays (NCAs) with desired concave diameters. A layer of aligned TiO2 NTs was fabricated on the surface of aluminum nano-concave arrays (Al...
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) ; Moniri Javadhesari, S ; Mohammadnejad, S ; khodadustan, E ; Raise, A ; Akbarpour, M. R ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
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....
Evaluation of antibacterial behavior of in situ grown CuO-GO nanocomposites
, Article Materials Today Communications ; Volume 28 , 2021 ; 23524928 (ISSN) ; Fattahi Nafchi Fatahi, R ; Sangpour, P ; Bagheri, M ; Rahimi, T ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
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)...