Search for: scaffolds--biology
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    An electroconductive, thermosensitive, and injectable chitosan/pluronic/gold-decorated cellulose nanofiber hydrogel as an efficient carrier for regeneration of cardiac tissue

    , Article Materials ; Volume 15, Issue 15 , 2022 ; 19961944 (ISSN) Tohidi, H ; Maleki Jirsaraei, N ; Simchi, A ; Mohandes, F ; Emami, Z ; Fassina, L ; Naro, F ; Conti, B ; Barbagallo, F ; Sharif University of Technology
    MDPI  2022
    Myocardial infarction is a major cause of death worldwide and remains a social and healthcare burden. Injectable hydrogels with the ability to locally deliver drugs or cells to the damaged area can revolutionize the treatment of heart diseases. Herein, we formulate a thermo-responsive and injectable hydrogel based on conjugated chitosan/poloxamers for cardiac repair. To tailor the mechanical properties and electrical signal transmission, gold nanoparticles (AuNPs) with an average diameter of 50 nm were physically bonded to oxidized bacterial nanocellulose fibers (OBC) and added to the thermosensitive hydrogel at the ratio of 1% w/v. The prepared hydrogels have a porous structure with open... 

    ZnO-incorporated polyvinylidene fluoride/poly(ε-caprolactone) nanocomposite scaffold with controlled release of dexamethasone for bone tissue engineering

    , Article Applied Physics A: Materials Science and Processing ; Volume 128, Issue 8 , 2022 ; 09478396 (ISSN) FotouhiArdakani, F ; Mohammadi, M ; Mashayekhan, S ; Sharif University of Technology
    Springer Science and Business Media Deutschland GmbH  2022
    Here we report on the development of a hybrid nanofibrous scaffold made from polyvinylidene fluoride (PVDF) nanofibers embedding zinc oxide nanorods (ZnOns), and poly(ε-caprolactone) (PCL) nanofibers incorporating dexamethasone (DEX)-loaded chitosan nanoparticles using dual-electrospinning method. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and tensile analysis were carried out for physiochemical characterization of the scaffolds, followed by DEX release profile. In addition, an MTT assay was conducted to assess the viability of mouse bone marrow-derived mesenchymal stem cells (mBMSCs) on the hybrid nanofibrous scaffold.... 

    Green polymer nanocomposites for skin tissue engineering

    , Article ACS Applied Bio Materials ; 2022 ; 25766422 (ISSN) Shokrani, H ; Shokrani, A ; Jouyandeh, M ; Seidi, F ; Gholami, F ; Kar, S ; Munir, M. T ; Kowalkowska Zedler, D ; Zarrintaj, P ; Rabiee, N ; Saeb, M. R ; Sharif University of Technology
    American Chemical Society  2022
    Fabrication of an appropriate skin scaffold needs to meet several standards related to the mechanical and biological properties. Fully natural/green scaffolds with acceptable biodegradability, biocompatibility, and physiological properties quite often suffer from poor mechanical properties. Therefore, for appropriate skin tissue engineering and to mimic the real functions, we need to use synthetic polymers and/or additives as complements to green polymers. Green nanocomposites (either nanoscale natural macromolecules or biopolymers containing nanoparticles) are a class of scaffolds with acceptable biomedical properties window (drug delivery and cardiac, nerve, bone, cartilage as well as skin... 

    Synthesis and characterization of a chitosan/gelatin transparent film crosslinked with a combination of EDC/NHS for corneal epithelial cell culture scaffold with potential application in cornea implantation

    , Article International Journal of Polymeric Materials and Polymeric Biomaterials ; Volume 71, Issue 8 , 2022 , Pages 568-578 ; 00914037 (ISSN) Shahin, A ; Ramazani S. A, A ; Mehraji, S ; Eslami, H ; Sharif University of Technology
    Taylor and Francis Ltd  2022
    The diseases and disorders of the cornea may lead to blindness, and cornea transplantation has been an effective treatment in this regard. However, lack of cornea throughout the world makes this treatment difficult. Therefore, the first goal of the present study is to make a chitosan/gelatin hyaline film with NHS and EDC crosslinkers for transplanting the epithelial cells of the cornea. Two solutions of gelatin and chitosan were mixed homogeneously before crosslinking in ratios of 20/80, 30/70, 40/60, and 50/50 (Gel/Chi). After 24 hours, they were put in an oven to dry, then EDC and NHS were added to the mixture as crosslinker. Corneal epithelial cell morphology was assessed qualitatively... 

    Effect of pore geometry and loading direction on deformation mechanism of rapid prototyped scaffolds

    , Article Acta Materialia ; Volume 60, Issue 6-7 , 2012 , Pages 2778-2789 ; 13596454 (ISSN) Amirkhani, S ; Bagheri, R ; Zehtab Yazdi, A ; Sharif University of Technology
    Rapid prototyping is a promising technique for producing tissue engineering scaffolds due to its capacity to generate predetermined forms and structures featuring distinct pore architectures. The objective of this study is to investigate the influences of different pore geometries and their orientation with respect to the compressive loading direction on mechanical responses of scaffolds. Plastic models of scaffolds with cubic and hexagonal unit cells were fabricated by three-dimensional (3-D) printing. An in situ imaging technique was utilized to study the progressive compressive deformation of the scaffold models. In both cubic and hexagonal geometries, organized buckling patterns relevant... 

    Biological evaluation of a novel tissue engineering scaffold of Layered Double Hydroxides (LDHs)

    , Article Key Engineering Materials, 6 November 2011 through 9 November 2011 ; Volume 493-494 , November , 2012 , Pages 902-908 ; 10139826 (ISSN) ; 9783037852552 (ISBN) Fayyazbakhsh, F ; Solati Hashjin, M ; Shokrgozar, M. A ; Bonakdar, S ; Ganji, Y ; Mirjordavi, N ; Ghavimi, S. A ; Khashayar, P ; Sharif University of Technology
    Bone Tissue Engineering (BTE) composed of three main parts: scaffold, cells and signaling factors. Several materials and composites are suggested as a scaffold for BTE. Biocompatibility is one of the most important property of a BTE scaffold. In this work synthesis of a novel nanocomposite including layered double hydroxides (LDH) and gelatin is carried out and its biological properties were studied. The co-precipitation (pH=11) method was used to prepare the LDH powder, using calcium nitrate, Magesium nitrate and aluminum nitrate salts as starting materials. The resulted precipitates were dried. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron... 

    Chitosan-gelatin sheets as scaffolds for muscle tissue engineering

    , Article Artificial Cells, Nanomedicine and Biotechnology ; Volume 43, Issue 2 , Nov , 2015 , Pages 124-132 ; 21691401 (ISSN) Hajiabbas, M ; Mashayekhan, S ; Nazaripouya, A ; Naji, M ; Hunkeler, D ; Rajabi Zeleti, S ; Sharifiaghdas, F ; Sharif University of Technology
    Informa Healthcare  2015
    Hydrogels made of natural polymers [chitosan (CS) and gelatin (G)] have been prepared having mechanical properties similar to those of muscle tissues. In this study, the effect of polymer concentration and scaffold stiffness on the behavior of seeded muscle-derived cells (MDCs) on the CS-G hydrogel sheets has been evaluated. Both variables were found to be important in cell viability. Viability was assessed by observation of the cell morphology after 1 day as well as a 14-day MTT assay. The CS-G hydrogels were characterized using Fourier transform infrared (FTIR) analysis, which revealed evidences of strong intermolecular interactions between CS and G. Hydrogel samples with intermediate... 

    The synergistic effect of surface topography and sustained release of TGF-β1 on myogenic differentiation of human mesenchymal stem cells

    , Article Journal of Biomedical Materials Research - Part A ; Volume 104, Issue 7 , 2016 , Pages 1610-1621 ; 15493296 (ISSN) Moghadasi Boroujeni, S ; Mashayekhan, S ; Vakilian, S ; Ardeshirylajimi, A ; Soleimani, M ; Sharif University of Technology
    John Wiley and Sons Inc 
    A combination of topographical cues and controlled release of biochemical factors is a potential platform in controlling stem cells differentiation. In this study the synergistic effect of nanotopography and sustained release of biofunctional transforming growth factor beta 1 (TGF-β1) on differentiation of human Wharton's Jelly-derived mesenchymal stem cell (hWJ-derived UC-MSCs) toward myogenic lineage was investigated. In order to achieve a sustained release of TGF-β1, this factor was encapsulated within chitosan nanoparticles. Afterwards the aligned composite mats were fabricated using poly-E-caprolacton (PCL) containing TGF-β1-loaded chitosan nanoparticles and poly-L-lactic acid (PLLA).... 

    The nanofibrous PAN-PANi scaffold as an efficient substrate for skeletal muscle differentiation using satellite cells

    , Article Bioprocess and Biosystems Engineering ; Volume 39, Issue 7 , 2016 , Pages 1163-1172 ; 16157591 (ISSN) Hosseinzadeh, S ; Mahmoudifard, M ; Mohamadyar Toupkanlou, F ; Dodel, M ; Hajarizadeh, A ; Adabi, M ; Soleimani, M ; Sharif University of Technology
    Springer Verlag 
    Among polymers, polyaniline (PANi) has been introduced as a good candidate for muscle regeneration due to high conductivity and also biocompatibility. Herein, for the first time, we report the use of electrospun nanofibrous membrane of PAN-PANi as efficient scaffold for muscle regeneration. The prepared PAN-PANi electrospun nanofibrous membrane was characterized by scanning electron microscopy (SEM), Attenuated total reflectance fourier transform infrared spectroscopy (ATR-FTIR) and tensile examination. The softer scaffolds of non-composite electrospun nanofibrous PAN govern a higher rate of cell growth in spite of lower differentiation value. On the other hand, PAN-PANi electrospun... 

    Simulation of the effects of oxygen carriers and scaffold geometry on oxygen distribution and cell growth in a channeled scaffold for engineering myocardium

    , Article Mathematical Biosciences ; Volume 294 , 2017 , Pages 160-171 ; 00255564 (ISSN) Zehi Mofrad, A ; Mashayekhan, S ; Bastani, D ; Sharif University of Technology
    This study proposes a mathematical model to evaluate the impact of oxygen carriers and scaffold geometry on oxygen distribution and cell growth in a 3D cardiac construct using computational fluid dynamics (CFD). Flow equations, oxygen balance equation and cell balance equation were solved using special initial and boundary conditions. The modeling results revealed that 55% increase in cardiac cell density occurred by using 6.4% perfluorocarbon oxygen carrier (PFC) compared to pure culture medium without PFC supplementation. Moreover, the effects of the scaffold geometry on cell density were examined by changing the channel numbers and the construct length. A 30% increase in the average cells... 

    Optimized composition of nanocomposite scaffolds formed from silk fibroin and nano-TiO2 for bone tissue engineering

    , Article Materials Science and Engineering C ; Volume 79 , 2017 , Pages 783-792 ; 09284931 (ISSN) Johari, N ; Madaah Hosseini, H. R ; Samadikuchaksaraei, A ; Sharif University of Technology
    Natural silk fibroin (SF) polymer has biomedical and mechanical properties as a biomaterial for bone tissue engineering scaffolds. Freeze-dried porous nanocomposite scaffolds were prepared from silk fibroin and titanium dioxide (TiO2) nanoparticles as a bioactive reinforcing agent by a phase separation method. In order to fabricate SF/TiO2 scaffolds, 5, 10, 15 and 20 wt% of the TiO2 were added to the SF. The phase structure, functional groups and morphology of the scaffolds were evaluated using X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy techniques, respectively. Porosity of the scaffolds was measured by Archimedes' Principle. In addition,... 

    Modeling and optimization of gelatin-chitosan micro-carriers preparation for soft tissue engineering: using response surface methodology

    , Article Materials Science and Engineering C ; Volume 75 , 2017 , Pages 545-553 ; 09284931 (ISSN) Radaei, P ; Mashayekhan, S ; Vakilian, S ; Sharif University of Technology
    Electrospray ionization is a wide spread technique for producing polymeric microcarriers (MCs) by applying electrostatic force and ionic cross-linker, simultaneously. In this study, fabrication process of gelatin-chitosan MCs and its optimization using the Response Surface Methodology (RSM) is reported. Gelatin/chitosan (G/C) blend ratio, applied voltage and feeding flow rate, their individual and interaction effects on the diameter and mechanical strength of the MCs were investigated. The obtained models for diameter and mechanical strength of MCs have a quadratic relationship with G/C blend ratio, applied voltage and feeding flow rate. Using the desirability curve, optimized G/C blend... 

    Fabrication of hierarchically porous silk fibroin-bioactive glass composite scaffold via indirect 3D printing: Effect of particle size on physico-mechanical properties and in vitro cellular behavior

    , Article Materials Science and Engineering C ; Volume 103 , 2019 ; 09284931 (ISSN) Razaghzadeh Bidgoli, M ; Alemzadeh, I ; Tamjid, E ; Khafaji, M ; Vossoughi, M ; Sharif University of Technology
    Elsevier Ltd  2019
    In order to regenerate bone defects, bioactive hierarchically scaffolds play a key role due to their multilevel porous structure, high surface area, enhanced nutrient transport and diffusion. In this study, novel hierarchically porous silk fibroin (SF) and silk fibroin-bioactive glass (SF-BG) composite were fabricated with controlled architecture and interconnected structure, by combining indirect three-dimensional (3D) inkjet printing and freeze-drying methods. Further, the effect of 45S5 Bioactive glass particles of different sizes (<100 nm and 6 μm) on mechanical strength and cell behavior was investigated. The results demonstrated that the hierarchical structure in this scaffold was... 

    Stereolithography 3D bioprinting method for fabrication of human corneal stroma equivalent

    , Article Annals of Biomedical Engineering ; Volume 48, Issue 7 , June , 2020 , Pages 1955-1970 Mahdavi, S. S ; Abdekhodaie, M. J ; Kumar, H ; Mashayekhan, S ; Baradaran Rafii, A ; Kim, K ; Sharif University of Technology
    Springer  2020
    Abstract: 3D bioprinting technology is a promising approach for corneal stromal tissue regeneration. In this study, gelatin methacrylate (GelMA) mixed with corneal stromal cells was used as a bioink. The visible light-based stereolithography (SLA) 3D bioprinting method was utilized to print the anatomically similar dome-shaped structure of the human corneal stroma. Two different concentrations of GelMA macromer (7.5 and 12.5%) were tested for corneal stroma bioprinting. Due to high macromer concentrations, 12.5% GelMA was stiffer than 7.5% GelMA, which made it easier to handle. In terms of water content and optical transmittance of the bioprinted scaffolds, we observed that scaffold with... 

    Comparison of engineered cartilage based on BMSCs and chondrocytes seeded on PVA-PPU scaffold in a sheep model

    , Article Journal of Biomedical Materials Research - Part B Applied Biomaterials ; Volume 110, Issue 11 , 2022 , Pages 2411-2421 ; 15524973 (ISSN) Taghizadehjahed, M ; Sepahdar, A ; Rabiee, N ; Nazbar, A ; Farzad Mohajeri, S ; Dehghan, M. M ; Shokrgozar, M. A ; Majidi, M ; Mardjanmehr, S. H ; Aminianfar, H ; Akbari Javar, H ; Bonakdar, S ; Sharif University of Technology
    John Wiley and Sons Inc  2022
    In this study, polyvinyl alcohol hydrogel chains were crosslinked by polyurethane in order to synthesize a suitable substrate for cartilage lesions. The substrate was fully characterized, and in vitro and in vivo investigations were conducted based on a sheep model. In vitro tests were performed based on the chondrocyte cells with the Alcian Blue and safranin O staining in order to prove the presence of proteoglycan on the surface of the synthesized substrate, which has been secreted by cultures of chondrocytes. Furthermore, the expression of collagen type I, collagen type II, aggrecan, and Sox9 was presented in the chondrocyte cultures on the synthesized substrate through RT-PCR. In... 

    In vitro study of hydroxyapatite/polycaprolactone (HA/PCL) nanocomposite synthesized by an in situ sol-gel process

    , Article Materials Science and Engineering C ; Volume 33, Issue 1 , 2013 , Pages 390-396 ; 09284931 (ISSN) Rezaei, A ; Mohammadi, M. R ; Sharif University of Technology
    Hydroxyapatite (HA) is the most substantial mineral constituent of a bone which has been extensively used in medicine as implantable materials, owing to its good biocompatibility, bioactivity high osteoconductive, and/or osteoinductive properties. Nevertheless, its mechanical property is not utmost appropriate for a bone substitution. Therefore, a composite consist of HA and a biodegradable polymer is usually prepared to generate an apt bone scaffold. In the present work polycaprolactone (PCL), a newly remarkable biocompatible and biodegradable polymer, was employed as a matrix and hydroxyapatite nanoparticles were used as a reinforcement element of the composite. HA/PCL nanocomposites were... 

    Fabrication of biocompatible titanium scaffolds using space holder technique

    , Article Journal of Materials Science: Materials in Medicine ; Volume 23, Issue 10 , 2012 , Pages 2483-2488 ; 09574530 (ISSN) Dezfuli, S. N ; Sadrnezhaad, S. K ; Shokrgozar, M. A ; Bonakdar, S ; Sharif University of Technology
    Springer  2012
    Open-pore titanium scaffolds were fabricated by sintering of compressed mixtures of TiH1.924 and urea. Spherical and irregular shaped space holders were used to investigate the effect of pore shape on cellular behavior. After removal of the space holder, the shape of the spacers was replicated to the pores. Average diameter of the pores was in the range of 300-600 lm. SEM images showed that titanium hydride resulted in higher surface roughness and larger micro porosities than pure titanium. In vitro evaluationswere carried out by using MTT assay, measuring alkaline phosphatase activity and alizarin red staining in flow perfusion bioreactor for cell culture. Observations revealed excellent... 

    The different fate of satellite cells on conductive composite electrospun nanofibers with graphene and graphene oxide nanosheets

    , Article Biomedical Materials (Bristol) ; Volume 11, Issue 2 , 2016 ; 17486041 (ISSN) Mahmoudifard, M ; Soleimani, M ; Hatamie, S ; Zamanlui, S ; Ranjbarvan, P ; Vossoughi, M ; Hosseinzadeh, S ; Sharif University of Technology
    Institute of Physics Publishing  2016
    Electrospinning of composite polymer solutions provides fantastic potential to prepare novel nanofibers for use in a variety of applications. The addition of graphene (G) and graphene oxide (GO) nanosheets to bioactive polymers was found to enhance their conductivity and biocompatibility. Composite conductive nanofibers of polyaniline (PANI) and polyacrylonitrile (PAN) with G and GO nanosheets were prepared by an electrospinning process. The fabricated membranes were investigated by physical and chemical examinations including scanning electron microscopy (SEM), Raman spectroscopy, x-ray diffraction (XRD) and tensile assay. The muscle satellite cells enriched by a pre-plating technique were... 

    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
    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... 

    Preparation of biodegradable gelatin/PVA porous scaffolds for skin regeneration

    , Article Artificial Cells, Nanomedicine and Biotechnology ; Volume 45, Issue 5 , 2017 , Pages 928-935 ; 21691401 (ISSN) Mahnama, H ; Dadbin, S ; Frounchi, M ; Rajabi, S ; Sharif University of Technology
    Taylor and Francis Ltd  2017
    Porous scaffolds composed of gelatin/poly (vinyl alcohol), (Gel/PVA), were prepared using combination of freeze gelation and freeze drying methods. The effect of polymer concentration, gelatin/PVA ratio, and glutaraldehyde/gelatin ratio (GA/Gel) was investigated on morphology of pores, swelling ratio, biodegradation, and skin cell culture. At optimum preparation conditions the scaffolds had uniform pore size distributions showing high swelling ratio of 23.6. The scaffolds were of biodegradable nature and almost degraded in 28 days. Human dermal fibroblast cells (HDF) were cultured on the scaffolds and MTS assay was conducted to evaluate the influence of PVA on growth and proliferation of the...