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The coupled microfluidic microbial electrochemical cell as a self-powered biohydrogen generator
, Article Journal of Power Sources ; Volume 451 , 2020 ; Mardanpour, M. M ; Yaghmaei, S ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Due to the importance of hydrogen as an effective antioxidant for its applications in therapy, this research reports the fabrication of a coupled microfluidic microbial electrochemical cell (MXC), including microfluidic microbial fuel cells (MFCs) and a microfluidic microbial electrolysis cell (MEC) series in order to perform it as a self-powered biohydrogen generator. Being able to be a platform of implantable medical devices, utilization a non-phatogenic strain of Escherichia coli as the biocatalyst in order to exploit the embodied energy from human blood and excrement and finally the use of cheap and facile materials (<$2 per device) are the exceptional features of the system. The...
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...
Synthesis photocatalytic TiO2/ZnO nanocomposite and investigation through anatase, wurtzite and ZnTiO3 phases antibacterial behaviors
, Article Journal of Nano Research ; Volume 51 , 2018 , Pages 69-77 ; 16625250 (ISSN) ; Ghorbani, M ; Sharif University of Technology
Trans Tech Publications Ltd
2018
Abstract
Titanium dioxide is prepared by sol gel method from titanium tetraisopropoxide (TTIP) as precursor and likewise zinc oxide is prepared by sol gel method from zinc acetate dehydrate (ZAD) as precursor. The composite sols are prepared in three different molar ratios 90TiO2:10ZnO, 70TiO2:30ZnO and 50TiO2:50ZnO. Thin film deposition is carried out by dip coating technique. Crystal structure, surface morphology and photocatalytic activity of the prepared nanocomposite thin films are investigated. The antibacterial activity of the prepared nanocomposite thin film against E-coli ATCC 25922 bacteria is examined by placing the thin film in standard aqueous E-coli medium under UV light for 1, 2, 3 and...
Synthesis of titania/carbon nanotube heterojunction arrays for photoinactivation of E. coli in visible light irradiation
, Article Carbon ; Volume 47, Issue 14 , 2009 , Pages 3280-3287 ; 00086223 (ISSN) ; Abdolahad, M ; Abdi, Y ; Mohajerzadeh, S ; Sharif University of Technology
2009
Abstract
TiO2/multi-wall carbon nanotube (MWNT) heterojunction arrays were synthesized and immobilized on Si(0 0 1) substrate as photocatalysts for inactivation of Escherichia coli bacteria. The vertically aligned MWNT arrays were grown on ∼5 nm Ni thin film deposited on the Si by using plasma enhanced chemical vapor deposition at 650 °C. Then, the MWNTs were coated by TiO2 using dip-coating sol-gel method. Post annealing of the TiO2/MWNTs at 400 °C resulted in crystallization of the TiO2 coating and formation of Ti-C and Ti-O-C carbonaceous bonds at the heterojunction. The visible light-induced photoinactivation of the bacteria increased from MWNTs to TiO2 to TiO2/MWNTs, in which the bacteria could...
Synthesis of nanobentonite–poly(vinyl alcohol)–bacterial cellulose nanocomposite by electrospinning for wound healing applications
, Article Physica Status Solidi (A) Applications and Materials Science ; Volume 217, Issue 6 , 2020 ; Ghanbari, H ; Mahmoudi, N ; Haramshahi, S. M. A ; Javadpour, J ; Sharif University of Technology
Wiley-VCH Verlag
2020
Abstract
Polymer-based composites are used for wound healing applications. This work aims to prepare an inorganic-polymer nanocomposite based on bentonite, poly(vinyl alcohol), and bacterial cellulose by electrospinning for wound healing. The nanocomposite is synthesized using a solution intercalation technique, with 1–2 wt% nanobentonite concentration variation. The effects of commercial and laboratory-synthesized nanobentonite as well as the extract of the green walnut shell (EGWS) are examined and characterized by different techniques. The addition of nanobentonite increases the average size of fibers and tensile strength up to 200 nm and more than 15 MPa, respectively, due to the presence of...
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...
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...
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;...
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....
Structural characterization of a rhamnolipid-type biosurfactant produced by Pseudomonas aeruginosa MR01: Enhancement of di-rhamnolipid proportion using gamma irradiation
, Article Colloids and Surfaces B: Biointerfaces ; Volume 81, Issue 2 , 2010 , Pages 397-405 ; 09277765 (ISSN) ; Abassi, H ; Ahmadkhaniha, R ; Roostaazad, R ; Masoomi, F ; Zahiri, H. S ; Ahmadian, G ; Vali, H ; Noghabi, K. A ; Sharif University of Technology
2010
Abstract
We previously reported that MR01, an indigenous strain of Pseudomonas aeruginosa, was able to produce a rhamnolipid-type biosurfactant. Here, we attempted to define the structural properties of this natural product. The analysis of the extracted biosurfactant by thin-layer chromatography (TLC) revealed the presence of two compounds corresponding to those of authentic mono- and di-rhamnolipid. The identity of two structurally distinguished rhamnolipids was confirmed by 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. Liquid chromatography/mass spectrometry (LC/MS) of extracted biosurfactant revealed up to seventeen different rhamnolipid congeners. Further quantification showed...
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...
Storage of Ag nanoparticles in pore-arrays of SU-8 matrix for antibacterial applications
, Article Journal of Physics D: Applied Physics ; Volume 42, Issue 13 , 2009 ; 00223727 (ISSN) ; Abdolahad, M ; Asadi, R ; Sharif University of Technology
2009
Abstract
Silver nanoparticles (NPs) stored in pore-arrays (pa) SU-8 photoresist layer were utilized as an antibacterial nanocomposition against E. coli bacteria. The pa-SU-8 matrix was fabricated by an optical interference lithography method resulting in small pores with a diameter of ∼50 nm and a depth of ∼100 nm. The Ag NPs were deposited on the soft polymeric matrix at different drying temperatures of 50 and 90 °C. X-ray photoelectron spectroscopy showed that the deposited silver NPs were substantially in the metallic state, independent from the drying condition. However, the concentration of the immobilized Ag NPs on the film surface increased (by a factor of 2.5) at the higher drying...
Statistical screening of medium components for recombinant production of Pseudomonas aeruginosa ATCC 9027 rhamnolipids by nonpathogenic cell factory pseudomonas putida KT2440
, Article Molecular Biotechnology ; Vol. 56, issue. 2 , 2014 , p. 175-191 ; Jahanmiri, A ; Eslamloueyan, R ; Niazi, A ; Ayatollahi, S. S ; Aram, F ; Mahmoodi, M ; Hortamani, A ; Sharif University of Technology
Abstract
Rhamnolipids (RLs) produced by the opportunistic human pathogen Pseudomonas aeruginosa are considered as potential candidates for the next generation of surfactants. Large-scale production of RLs depends on progress in strain engineering, medium design, operating strategies, and purification procedures. In this work, the rhlAB genes extracted from a mono-RLs-producing strain of P. aeruginosa (ATCC 9027) were introduced to an appropriate safety host Pseudomonas putida KT2440. The capability of the recombinant strain was evaluated in various media. As a prerequisite for optimal medium design, a set of 32 experiments was performed in two steps for screening a number of macro-nutritional...
Solar-assisted bacterial disinfection and removal of contaminants of emerging concern by Fe2+-activated HSO5- vs. S2O82- in drinking water
, Article Applied Catalysis B: Environmental ; Volume 248 , 2019 , Pages 62-72 ; 09263373 (ISSN) ; Giannakis, S ; Marjanovic, M ; Kohantorabi, M ; Gholami, M. R ; Grandjean, D ; de Alencastro, L. F ; Pulgarín, C ; Sharif University of Technology
Elsevier B.V
2019
Abstract
This research demonstrates the feasibility to enhance solar disinfection (SODIS) treatment by addition of peroxymonosulfate (PMS) and peroxydisulfate (PDS) by the generation of sulfate (and hydroxyl) radicals through different activation routes. The different promoters were i) sunlight irradiation, ii) mild heat (40 °C), and iii) μM amounts of Fe2+, all present during actual field SODIS experiments, or voluntarily added alongside PMS/PDS. In a first approach, the promoters were studied separately, in pairs and finally all together in a combined process (CP). In all the cases, PMS showed a higher efficiency than PDS in E. coli removal, requiring lower concentration and a faster reaction time...
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...
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...
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) ; Abdolahad, M ; Abdi, Y ; Mohajerzadeh, S ; Sharif University of Technology
2011
Abstract
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...
Silver nanoparticles with gelatin nanoshells: Photochemical facile green synthesis and their antimicrobial activity
, Article Journal of Nanoparticle Research ; Volume 13, Issue 10 , October , 2011 , Pages 4647-4658 ; 13880764 (ISSN) ; Soleyman, R ; Sharif University of Technology
2011
Abstract
In the current study, a facile green synthesis of silver-gelatin core-shell nanostructures (spherical, spherical/cubic hybrid, and cubic, DLS diameter: 4.1-6.9 nm) is reported via the wet chemical synthesis procedure. Sunlight-UV as an available reducing agent cause mild reduction of silver ions into the silver nanoparticles (Ag-NPs). Gelatin protein, as an effective capping/shaping agent, was used in the reaction to self-assemble silver nanostructures. The formation of silver nanostructures and their self-assembly pattern was confirmed by SEM, AFM, and TEM techniques. Further investigations were carried out using zeta-potential, UV-Vis, FTIR, GPC, and TGA/DTG/DTA data. The prepared Ag-NPs...
Shape-controlled silver NPs for shape-dependent biological activities
, Article Micro and Nano Letters ; Volume 12, Issue 9 , 2017 , Pages 647-651 ; 17500443 (ISSN) ; Yazdanpanah, A ; Abrishamkar, A ; Moztarzadeh, F ; Ramedani, A ; Pouraghaie, S ; Shirinzadeh, H ; Samadikuchaksaraei, A ; Chauhan, N. P. S ; Hopkinson, L ; Sefat, F ; Mozafari, M ; Sharif University of Technology
Abstract
The most important issue during synthesis of nanoparticles (NPs) is to avoid particle agglomeration and adhesion. There have been several attempts to use special substances such as organic surfactants, polymers and stable ligands for this purpose. In this study, silver NPs were synthesised with and without gelatin macromolecules, as a green natural biopolymer, which resulted in NPs with varying shapes and sizes. The effect of morphological characteristics on the antibacterial and antifungal properties of the synthesised NPs were studied, by comparing Gram-negative (Escherichia coli) versus Gram-positive (Staphylococcus aureus) bacteria as well as fungi (Candida albicans) by calculation of...
Self-accumulated Ag nanoparticles on mesoporous TiO2 thin film with high bactericidal activities
, Article Surface and Coatings Technology ; Volume 204, Issue 21-22 , August , 2010 , Pages 3676-3683 ; 02578972 (ISSN) ; Ghaderi, E ; Sharif University of Technology
Abstract
Antibacterial activity of sol-gel synthesized Ag-TiO2 nanocomposite layer (30nm) deposited on rough anatase (a) TiO2 thin film (~200nm in thickness) was investigated against Escherichia coli bacteria, in dark and also in exposure to UV light. The nanocomposite thin films were transparent with a surface plasmon resonance absorption band at a wavelength of 410nm. The metallic silver nanoparticles with an average diameter of 30nm and fcc crystalline structure were self-accumulated on surface of a mesoporous and aqueous TiO2 layer with a capillary pore structure having a pore radius of 3.0nm. By adding the silver nanoparticles in the TiO2 layer, recombination of the photoexcited electron-hole...