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    Interaction of 3D dewetting nanodroplets on homogeneous and chemically heterogeneous substrates

    , Article Journal of Physics Condensed Matter ; Vol. 26, Issue. 22 , 2014 ; ISSN: 09538984 Asgari, M ; Moosavi, A ; Sharif University of Technology
    Abstract
    Long-time interaction of dewetting nanodroplets is investigated using a long-wave approximation method. Although three-dimensional (3D) droplets evolution dynamics exhibits qualitative behavior analogous to two-dimensional (2D) dynamics, there is an extensive quantitative difference between them. 3D dynamics is substantially faster than 2D dynamics. This can be related to the larger curvature and, as a consequence, the larger Laplace pressure difference between the droplets in 3D systems. The influence of various chemical heterogeneities on the behavior of droplets has also been studied. In the case of gradient surfaces, it is shown how the gradient direction could change the dynamics. For a... 

    Rigidity of transmembrane proteins determines their cluster shape

    , Article Physical Review E - Statistical, Nonlinear, and Soft Matter Physics ; Volume 93, Issue 1 , 2016 ; 15393755 (ISSN) Jafarinia, H ; Khoshnood, A ; Jalali, M. A ; Sharif University of Technology
    American Physical Society 
    Abstract
    Protein aggregation in cell membrane is vital for the majority of biological functions. Recent experimental results suggest that transmembrane domains of proteins such as α-helices and β-sheets have different structural rigidities. We use molecular dynamics simulation of a coarse-grained model of protein-embedded lipid membranes to investigate the mechanisms of protein clustering. For a variety of protein concentrations, our simulations under thermal equilibrium conditions reveal that the structural rigidity of transmembrane domains dramatically affects interactions and changes the shape of the cluster. We have observed stable large aggregates even in the absence of hydrophobic mismatch,... 

    Double network hydrogel of sodium alginate/polyacrylamide cross-linked with POSS: Swelling, dye removal and mechanical properties

    , Article International Journal of Biological Macromolecules ; Volume 129 , 2019 , Pages 187-197 ; 01418130 (ISSN) Bahrami, Z ; Akbari, A ; Eftekhari Sis, B ; Sharif University of Technology
    Elsevier B.V  2019
    Abstract
    In this work, for the first time, we presented a novel design strategy to fabricate a new type of Octa-aminopropyl polyhedral oligomeric silsesquioxane hydrochloride salt (OA-POSS)-based Alg/PAAm DN gels, consisting of PAAm gel as the first chemical network and Alg/OA-POSS gel as the second chemical-physical network. Incorporation of OA-POSS nanoparticles with various feed ratio into the second network not only led to form strong coordination interactions but also in comparison to the other Alg/PAAm gels demonstrated superior mechanical properties. pH, temperature, contact time and salt effects parameters were studied on the swelling and dye removal properties of the synthesized DN hybrid... 

    Protein-nanoparticle interactions: Opportunities and challenges

    , Article Chemical Reviews ; Volume 111, Issue 9 , June , 2011 , Pages 5610-5637 ; 00092665 (ISSN) Mahmoudi, M ; Lynch, I ; Ejtehadi, M. R ; Monopoli, M. P ; Bombelli, F. B ; Laurent, S ; Sharif University of Technology
    2011
    Abstract
    The significant role of protein nanoparticle interactions in nanomedicine and nanotoxicity is emerging recently through the identification of the nanoparticles (NP) protein (biomolecule) corona. The dynamic layer of proteins and/or other biomolecules adsorbed to the nanoparticle surface determines how a NP interacts with living systems and thereby modifies the cellular responses to the NP. Ehrenberg and co-workers used cultured endothelium cells as a model for vascular transport of polystyrene NP with various functional groups, which showed that the capacity of the various NP surfaces to adsorb proteins was indicative of their tendency to associate with cells. The quantification of the... 

    Utilization of molecular dynamics simulation coupled with experimental assays to optimize biocompatibility of an electrospun PCL/PVA scaffold

    , Article PLoS ONE ; Volume 12, Issue 1 , 2017 ; 19326203 (ISSN) Sarmadi, M ; Shamloo, A ; Mohseni, M ; Sharif University of Technology
    Public Library of Science  2017
    Abstract
    The main focus of this study is to address the possibility of using molecular dynamics (MD) simulation, as a computational framework, coupled with experimental assays, to optimize composite structures of a particular electrospun scaffold. To this aim, first, MD simulations were performed to obtain an initial theoretical insight into the capability of heterogeneous surfaces for protein adsorption. The surfaces were composed of six different blends of PVA (polyvinyl alcohol) and PCL (polycaprolactone) with completely unlike hydrophobicity. Next, MTT assay was performed on the electrospun scaffolds made from the same percentages of polymers as in MD models to gain an understanding of the... 

    Plant protein-based hydrophobic fine and ultrafine carrier particles in drug delivery systems

    , Article Critical Reviews in Biotechnology ; Volume 38, Issue 1 , 2018 , Pages 47-67 ; 07388551 (ISSN) Malekzad, H ; Mirshekari, H ; Sahandi Zangabad, P ; Moosavi Basri, S. M ; Baniasadi, F ; Sharifi Aghdam, M ; Karimi, M ; Hamblin, M. R ; Sharif University of Technology
    Taylor and Francis Ltd  2018
    Abstract
    For thousands of years, plants and their products have been used as the mainstay of medicinal therapy. In recent years, besides attempts to isolate the active ingredients of medicinal plants, other new applications of plant products, such as their use to prepare drug delivery vehicles, have been discovered. Nanobiotechnology is a branch of pharmacology that can provide new approaches for drug delivery by the preparation of biocompatible carrier nanoparticles (NPs). In this article, we review recent studies with four important plant proteins that have been used as carriers for targeted delivery of drugs and genes. Zein is a water-insoluble protein from maize; Gliadin is a 70% alcohol-soluble... 

    Modification of bacterial cellulose/keratin nanofibrous mats by a tragacanth gum-conjugated hydrogel for wound healing

    , Article International Journal of Biological Macromolecules ; Volume 134 , 2019 , Pages 280-289 ; 01418130 (ISSN) Azarniya, A ; Tamjid, E ; Eslahi, N ; Simchi, A ; Sharif University of Technology
    Elsevier B.V  2019
    Abstract
    To enhance physicomechanical properties and bioactivity of fibrous membranes for wound dressing and tissue engineering applications, novel composite scaffolds consisting of fibrous mats and thermosensitive hydrogel particles were prepared by concurrent electrospinning and electrospraying technique. The composite scaffolds were composed of keratin/bacterial cellulose fibers (150 ± 43 nm) which are hybridized with hydrogel particles (500 nm to 2 μm) based on nonionic triblock copolymers conjugated with Tragacanth gum (TG). FTIR and H-NMR studies indicated ester reactions between carboxylated copolymers and TG through carbodiimide crosslinker chemistry. The hydrogel particles were uniformly... 

    Nanoparticles migration due to thermophoresis and Brownian motion and its impact on Ag-MgO/water hybrid nanofluid natural convection

    , Article Powder Technology ; Volume 375 , 20 September , 2020 , Pages 493-503 Goudarzi, S ; Shekaramiz, M ; Omidvar, A ; Golab, E ; Karimipour, A ; Karimipour, A ; Sharif University of Technology
    Elsevier B.V  2020
    Abstract
    The present study aims to investigate the impact of nanoparticle migration due to Brownian motion and thermophoresis on Ag-MgO/Water hybrid nanofluid natural convection. An enclosure with sinusoidal wavy walls is considered for this investigation; right and cold walls of this enclosure are in constant temperature while the upper and bottom walls are insulated. This simulation follows Buongiorno's mathematical model; Brownian and thermophoresis diffusion of Ag occurs in MgO-Water nanofluid while the diffusion of MgO happens in Ag-water nanofluid. The result indicates that Nu number increments up to 11% by increasing thermophoresis diffusion for both nanoparticles. Also, increasing Brownian... 

    Regio- and diastereoselective synthesis of novel polycyclic pyrrolo[2,1- a]isoquinolines bearing indeno[1,2- b]quinoxaline moieties by a three-component [3+2]-cycloaddition reaction

    , Article Synlett ; Volume 31, Issue 3 , 2020 , Pages 267-271 Matloubi Moghaddam, F ; Moafi, A ; Jafari, B ; Vilinger, A ; Langer, P ; Sharif University of Technology
    Georg Thieme Verlag  2020
    Abstract
    A regio- and diastereoselective synthesis of 2,3-dihydro-10b′ H -spiro[indeno[1,2- b ]quinoxaline-11,1′-pyrrolo[2,1- a ]isoquinoline]-2′,3′-diylbis(phenylmethanone) derivatives containing four contiguous chiral stereocenters was achieved through 1,3-dipolar cycloaddition of isoquinolinium N -ylides in a one-pot three-component reaction. The desired products were obtained in short reaction times and in moderate to high yields (up to 92%) under relatively mild reaction conditions. The structure and relative stereochemistry of the desired product was confirmed by X-ray diffraction analysis. © 2020 Georg Thieme Verlag. All rights reserved  

    Fabrication and characterization of low-cost, bead-free, durable and hydrophobic electrospun membrane for 3D cell culture

    , Article Biomedical Microdevices ; Volume 19, Issue 4 , 2017 ; 13872176 (ISSN) Moghadas, H ; Saidi, M. S ; Kashaninejad, N ; Kiyoumarsioskouei, A ; Trung Nguyen, N ; Sharif University of Technology
    Abstract
    This paper reports the fabrication of electrospun polydimethylsiloxane (PDMS) membranes/scaffolds that are suitable for three-dimensional (3D) cell culture. Through modification the ratio between PDMS and polymethylmethacrylate (PMMA) as carrier polymer, we report the possibility of increasing PDMS weight ratio of up to 6 for electrospinning. Increasing the PDMS content increases the fiber diameter, the pore size, and the hydrophobicity. To our best knowledge, this is the first report describing beads-free, durable and portable electrospun membrane with maximum content of PDMS suitable for cell culture applications. To show the proof-of-concept, we successfully cultured epithelial lung... 

    Implementing a superhydrophobic substrate in immersed solvent–supported microextraction as a novel strategy for determination of organic pollutants in water samples

    , Article Ecotoxicology and Environmental Safety ; Volume 163 , 2018 , Pages 104-110 ; 01476513 (ISSN) Baktash, M. Y ; Asem Yousefi, A ; Bagheri, H ; Sharif University of Technology
    Academic Press  2018
    Abstract
    In this research, a new approach for extraction and determination of polycyclic aromatic hydrocarbons from sea and rain water samples was developed by implementing a superhydrophobic substrate and consuming the least amount of solvent. This version of solvent–supported microextraction enabled us to perform the procedure in the immersion mode with the slightest troubles arising from water leakage into the gas chromatography. The superhydrophobic property leads to the fixation of extracting solvent on the substrate surface during water sampling. To prepare a superhydrophobic substrate, a piece of melamine foam was coated by tannic acid and silica nanoparticles using methyltrimethoxysilane and... 

    Noble metal nanostructures in optical biosensors: basics, and their introduction to anti-doping detection

    , Article TrAC - Trends in Analytical Chemistry ; Volume 100 , 2018 , Pages 116-135 ; 01659936 (ISSN) Malekzad, H ; Sahandi Zangabad, P ; Mohammadi, H ; Sadroddini, M ; Jafari, Z ; Mahlooji, N ; Abbaspour, S ; Gholami, S ; Ghanbarpoor, M ; Pashazadeh, R ; Beyzavi, A ; Karimi, M ; Hamblin, M. R ; Sharif University of Technology
    Elsevier B.V  2018
    Abstract
    Nanotechnology has illustrated significant potentials in biomolecular-sensing applications; particularly its introduction to anti-doping detection is of great importance. Illicit recreational drugs, substances that can be potentially abused, and drugs with dosage limitations according to the prohibited lists announced by the World Antidoping Agency (WADA) are becoming of increasing interest to forensic chemists. In this review, the theoretical principles of optical biosensors based on noble metal nanoparticles, and the transduction mechanism of commonly-applied plasmonic biosensors are covered. We review different classes of recently-developed plasmonic biosensors for analytic determination... 

    Bilayered heparinized vascular graft fabricated by combining electrospinning and freeze drying methods

    , Article Materials Science and Engineering C ; Volume 94 , 2019 , Pages 1067-1076 ; 09284931 (ISSN) Khayat Norouzi, S ; Shamloo, A ; Sharif University of Technology
    Elsevier Ltd  2019
    Abstract
    Small diameter vascular grafts (<6 mm) are highly demanded for patients suffering from severe occluded arteries to be used as a bypass or substituted conduit. Fabricating a graft with appropriate structural, mechanical and cell growth properties which has simultaneously anti-thrombogenic trait is a challenge nowadays. Here, we proposed a bilayer heparinized vascular graft that can mimic the structural and mechanical characteristics close to those of the native coronary artery by combining electrospinning and freeze drying methods. In this study, the inner layer was made by co-electrospinning of synthetic polymer, poly-caprolactone (PCL) and the natural polymer, gelatin (Gel). Also, heparin... 

    Bilayered heparinized vascular graft fabricated by combining electrospinning and freeze drying methods

    , Article Materials Science and Engineering C ; Volume 94 , 2019 , Pages 1067-1076 ; 09284931 (ISSN) Khayat Norouzi, S ; Shamloo, A ; Sharif University of Technology
    Elsevier Ltd  2019
    Abstract
    Small diameter vascular grafts (<6 mm) are highly demanded for patients suffering from severe occluded arteries to be used as a bypass or substituted conduit. Fabricating a graft with appropriate structural, mechanical and cell growth properties which has simultaneously anti-thrombogenic trait is a challenge nowadays. Here, we proposed a bilayer heparinized vascular graft that can mimic the structural and mechanical characteristics close to those of the native coronary artery by combining electrospinning and freeze drying methods. In this study, the inner layer was made by co-electrospinning of synthetic polymer, poly-caprolactone (PCL) and the natural polymer, gelatin (Gel). Also, heparin... 

    Discovery of a tetracyclic indole alkaloid that postpones fibrillation of hen egg white lysozyme protein

    , Article International Journal of Biological Macromolecules ; Volume 183 , 2021 , Pages 1939-1947 ; 01418130 (ISSN) Ashrafian, H ; Zadeh, E.H ; Tajbakhsh, M ; Majid, N ; Srivastava, G.N ; Khan, R.H ; Sharif University of Technology
    Elsevier B.V  2021
    Abstract
    Protein aggregation, such as amyloid fibril formation, is molecular hallmark of many neurodegenerative disorders including Alzheimer's, Parkinson's, and Prion disease. Indole alkaloids are well-known as the compounds having the ability to inhibit protein fibrillation. In this study, we experimentally and computationally have investigated the anti-amyloid property of a derivative of a synthesized tetracyclic indole alkaloid (TCIA), possessing capable functional groups. The fibrillation reaction of Hen White Egg Lysozyme (HEWL) was performed in absence and presence of the indole alkaloid. For quantitative analysis, we used Thioflovin T binding assay which showed ~50% reduction in fibril... 

    Fabrication and characterization of biaxially electrospun collagen/alginate nanofibers, improved with Rhodotorula mucilaginosa sp. GUMS16 produced exopolysaccharides for wound healing applications

    , Article International Journal of Biological Macromolecules ; Volume 196 , 2022 , Pages 194-203 ; 01418130 (ISSN) Ashraf, S. S ; Parivar, K ; Hayati Roodbari, N ; Mashayekhan, S ; Amini, N ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    Fabrication of scaffolds with enhanced mechanical properties and desirable cellular compatibility is critical for numerous tissue engineering applications. This study was aimed at fabrication and characterization of a nanofiber skin substitute composed of collagen (Col)/sodium alginate (SA)/ polyethylene oxide (PEO)/Rhodotorula mucilaginosa sp. GUMS16 produced exopolysaccharides (EPS) were prepared using the biaxial electrospinning technique. This study used collagen extracted from the bovine tendon as a natural scaffold, sodium alginate as an absorber of excess wound fluids, and GUMS16 produced exopolysaccharides as an antioxidant. Collagen was characterized using FTIR and EDS analyses. The... 

    Development of a novel nano-sized anti-VEGFA nanobody with enhanced physicochemical and pharmacokinetic properties

    , Article Artificial Cells, Nanomedicine and Biotechnology ; Volume 46, Issue 7 , 2018 , Pages 1402-1414 ; 21691401 (ISSN) Khodabakhsh, F ; Norouzian, D ; Vaziri, B ; Ahangari Cohan, R ; Sardari, S ; Mahboudi, F ; Behdani, M ; Mansouri, K ; Mehdizadeh, A ; Sharif University of Technology
    Abstract
    Since physiological and pathological processes occur at nano-environments, nanotechnology has considered as an efficient tool for designing of next generation specific biomolecules with enhanced pharmacodynamic and pharmacodynamic properties. In the current investigation, by control of the size and hydrodynamic volume at the nanoscale, for the first time, physicochemical and pharmacokinetic properties of an anti-VEGFA nanobody was remarkably improved by attachment of a Proline-Alanine-Serine (PAS) rich sequence. The results elucidated unexpected impressive effects of PAS sequence on physicochemical properties especially on size, hydrodynamics radius, and even solubility of nanobody. CD... 

    Magnetic, thermally stable, and superhydrophobic polyurethane sponge: A high efficient adsorbent for separation of the marine oil spill pollution

    , Article Chemosphere ; Volume 287 , 2022 ; 00456535 (ISSN) Habibi, N ; Pourjavadi, A ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    Herein, we demonstrated a facile method for the fabrication of magnetic and superhydrophobic polyurethane sponge with water contact angle of 159° as an adsorbent for cleanup the marine oil spill pollution. For this aim, a polyurethane sponge was coated with carbon black (CB), hexagonal boron nitride (h-BN)@Fe3O4, and acrylic resin and then characterized by different techniques. Owing to the chemical and thermal stability of h-BN and CB, the modified sponge was stable under corrosive conditions (pH = 1–14 and salt solutions) and at different temperatures (−12 °C–105 °C). In addition to common oils and organic solvents, we also used the real spilled oils containing monoaromatics and...