Search for: polycaprolactone
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    Study & Synthesis of Biocompatible Scaffolds for Animal Cell Cultures

    , M.Sc. Thesis Sharif University of Technology Riazi Esfahani, Bahar (Author) ; Vosoughi, Manouchehr (Supervisor) ; Alemzadeh, Iran (Co-Advisor) ; Pajoum Shariati, Ramin (Co-Advisor)
    Natural tissues of body consist of Extra Cellular Matrix (ECM) and cells. Scaffold produces a temporary matrix for cells and facilitates oxygen and nutrients transport which enhances tissue regeneration. Therefore, attempts in regeneration of tissues and organs by scaffolds attracted great interest in today’s researchs. Choosing scaffold fabrication method and its polymer type, play a key role in scaffold specifications as they determine scaffold properties. In this project electrospinning was chosen as the scaffold fabrication method which is because of the unique properties of scaffolds fabricated by this method and also its ability in producing micro and nano fibers. At first set of... 

    Synthesis of Hydroxyapatite Whisker and Nanorods/Polycaprolactone Composites and Scaffolds: In vitro & In vivo studies

    , M.Sc. Thesis Sharif University of Technology Lebasi, Mohammad Ali (Author) ; Mohammadi, Mohammad Reza (Supervisor)
    This work describes the effect of hydroxyapatite with different morphology including nanorods and whisker on the properties of hydroxyapatite/polycaprolactone (HA/PCL) composite. Biodegradable polymer/Hydroxyapatite (HA) composites with the morphology of nanorods and whisker of (HA) as bone replacement scaffolds are synthesized by sol-gel and hydrothermal methods, respectively with a Ca/P ratio of 1.67 and 20:80 (HA/PCL).The crystallization behavior and porosity of HA/PCL composite are studied by scanning electron microscope and X-Ray diffraction. The response of bone marrow-derived human mesenchymal stem cells (hMSCs) in terms of cell proliferation and differentiation to the osteoblastic... 

    Evaluation of Nanobiocomposite Based on Thermoplastic Starch for Bone Tissue Engineering Applications

    , M.Sc. Thesis Sharif University of Technology Taherimehr, Marzieh (Author) ; Bagheri, Reza (Supervisor) ; Maddah Hosseini, Hamid Reza (Supervisor)
    Development of new engineered materials for bone tissue engineering applications is rapidly growing. The most important characteristics of materials, which can be used for bone tissue engineering applications, are appropriate mechanical properties, degradation rate, swelling behavior, and bioactivity. The goal of the current investigation is to study the feasibility of incorporating a modified nano-biocomposite based on biodegradable thermoplastic starch for bone tissue engineering. Nano particles of ?-tricalcium phosphate and hydroxyapatite were incorporated for reinforcing the matrix as well as improving the bioactivity. A second biodegradable polymer, i.e. polycaprolactone, was used... 

    In Situ Synthesis of Nanorod Hydroxyapatite Reinforced Polycaprolactone Nanocomposite for Bone Tissue Engineering Application

    , M.Sc. Thesis Sharif University of Technology Moeini, Saeed (Author) ; Mohammadi, Mohammad Reza (Supervisor) ; Simchi, Abdol Reza (Supervisor)
    Hydroxyapatite is the most substantial inorganic constituent of bone tissue which displays splendid biocompability and bioactivity. Nevertheless, its mechanical properties is not utmost appropriate for a bone substitutes. Therefore, it is used to improve the mechanical properties of polymer matrix composite scaffolds. In the present work polycaprolactone as a polymeric matrix was employed to fabricate hydroxyapatite-polycaprolactone biocomposite scaffolds via in situ route. Solvothermal method was employed to synthesize in situ hydroxyapatite in polymer matrix. Porous scaffolds were fabricated via freeze-drying/porogen leaching. Physical, mechanical (compressive module and compressive... 

    Synthesis and Characterization of Nano-Composite Based on Supramolecuylar Poly Caprolactone/ Hydroxyapatite for Tissue Engineering Application

    , M.Sc. Thesis Sharif University of Technology Mehmanchi, Mohammad (Author) ; Bagheri, Reza (Supervisor) ; Shokrollahi, Parvin (Supervisor) ; Ataei, Mohammad (Co-Advisor)
    Synthetic polymers have a high capacity to provide and manufacture the pieces used in tissue engineering. However, optimizing the biocompatibility, bioresorbableility and mechanical properties simultaneous with processability of material is complicated and requires a lot of effort at designing different parts of the system. On the other hand, due to existence of secondary bonds (such as metal-ligand coordination or hydrogen bond) supramolecular polymers are able to respond to some stimuli such as temperature, pH, or pressure, which is important in terms of dynamic nature of interaction between the living cells and the external matrix of cell. Recently there have been extensive studies on... 

    Preparation and Characterization of Hydroxyapatite/Polycaprolactone Nanocomposites by Sol-gel Process

    , M.Sc. Thesis Sharif University of Technology Rezaei, Amirreza (Author) ; Mohammadi, Mohammad Reza (Supervisor)
    Hydroxyapatite (HA) is the most substantial mineral constituent of a bone which displays splendid biocompatibility and bioactivity 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 and nanorods were used as a reinforcement element of the composite. HA/PCL nanocomposites were synthesized by three new in-situ sol-gel processes using a diverse range of phosphorus and... 

    Optimization of Insulin Release from Beta Cells Using Hybrid Scaffold Bioengineering

    , M.Sc. Thesis Sharif University of Technology Ebrahimi, Negar (Author) ; Alemzadeh, Iran (Supervisor) ; Vossoughi, Manouchehr (Supervisor)
    Combined composites consisting of nanofibers and hydrogels were fabricated to grow cells in an environment that mimicked the extracellular matrix. Electrospan nanofibers were spun and hydrolyzed under optimized conditions consisting of polycaprolactone (PCL) and gelatin and then incorporated into alginate and gelatin hydrogels. Nanofibril-containing (NF / hydrogel) hydrogel hybrids were ligated by calcium chloride in the presence of encapsulated beta cells. The mechanical properties of NF / hydrogel scaffolds were significantly increased in proportion to the NF content in NF / hydrogels. Beta cells killed in NF / hydrogels showed higher adhesion to the matrix compared to samples without NF.... 

    Functionalized mesoporous silica-coated magnetic graphene oxide by polyglycerol-g-polycaprolactone with pH-responsive behavior: designed for targeted and controlled doxorubicin delivery

    , Article Journal of Industrial and Engineering Chemistry ; 2015 ; ISSN: 1226086X Pourjavadi, A ; Tehrani, Z. M ; Jokar, S ; Sharif University of Technology
    In the present work a novel multifunctional drug nanocarrier was prepared. Polyglycerol-. g-polycaprolactone was grafted on Mesoporous silica-coated magnetic graphene oxide. Doxorubicin, as anticancer drug, was loaded on this carrier. The in vitro drug release showed the controlled pH responsive behavior. At the endosomal pH (pH 5.5) the amount of drug release enhanced. This nanocarrier would have potential application in the tumor therapy owing to its biodegradability, controlled release and pH responsive behavior  

    Bio-based UV curable polyurethane acrylate: Morphology and shape memory behaviors

    , Article European Polymer Journal ; Volume 118 , 2019 , Pages 514-527 ; 00143057 (ISSN) Salkhi Khasraghi, S ; Shojaei, A ; Sundararaj, U ; Sharif University of Technology
    Elsevier Ltd  2019
    Smart bio-based shape memory polymers with high performance and fast response have the exciting potential to meet the growing need in biomedical applications. In this study, novel fast response UV-curable shape memory polyurethane acrylates (SMPUAs) comprising polycaprolactone diols (PCL-Diol), hexamethylene diisocyanate (HDI) and hydroxy-methyl methacrylate (HEMA) were synthesized by two-step bulk polymerization. Two series of PUAs with almost the same amount of hard segment content (HSC) were prepared with varying soft-segment molecular weight (2000, 3000, and 4000 g/mol) and different molar ratios of constituents. A mono-functional reactive diluent was used to control HSC and reduce the... 

    Development of a nano biosensor for anti-gliadin detection for Celiac disease based on suspension microarrays

    , Article Biomedical Physics and Engineering Express ; Volume 6, Issue 5 , August , 2020 Kharati, M ; Rabiee, M ; Rostami Nejad, M ; Aghamohammadi, E ; Asadzadeh Aghdaei, H ; Zali, M. R ; Rabiee, N ; Fatahi, Y ; Bagherzadeh, M ; Webster, T. J ; Sharif University of Technology
    IOP Publishing Ltd  2020
    Celiac disease is an autoimmune disorder represented by the ingestion of the gluten protein usually found in wheat, barley and rye. To date, ELISA has been the most accurate method for determining the presence of anti-gliadin, which is cumbersome, expensive (compared to a suspension microarray technique), and requires extensive sample preparation. In this study, in order to establish a more accurate assay to identify gliadin at lower concentrations, optical nano biosensors using an indirect immunoassay method for gliadin detection was designed and fabricated. For this, polycaprolactone (PCL) nano- to micro-beads were fabricated as a platform for the gliadin antigen which were optimized and... 

    Effect of Bioglass Particle Size and Titania Morphology on the Bioactivity and Kinetics of Tissue Growth in Three-Dimensional Poly(ɛ-Caprolactone) Scaffolds with Controlled Pore Structure Produced by 3D-Printing Process

    , Ph.D. Dissertation Sharif University of Technology Tamjid Shabestary, Elnaz (Author) ; Bagheri, Reza (Supervisor) ; Vossoughi, Manouchehr (Supervisor) ; Simchi, Abdolreza (Co-Advisor)
    Polycaprolactone (PCL) scaffolds and its composites containing bioactive glass particles (45S5) and TiO2 nanostructures with pre-defined and controlled external and internal architecture were prepared via an indirect three-dimensional (3D) printing process. The scaffolds had an interconnected structure with macro- (400-500 μm) and micro- (~25 μm) pores. Bioactivity, mechanical behavior and kinetics of tissue growth in 3D scaffolds were studied. The size effect of biogactive glass particles (6 μm, 250 nm, <100 nm) and morphology of titania nanostructures (spherical, tube, leaf-like, and flower-like particles) were elaborated. The biogactive glass particles with different sizes were prepared... 

    Combination of PRP (platelet Rich plasma)with Polymeric Scaffold for Cartilage Regeneration

    , M.Sc. Thesis Sharif University of Technology Rafiei, Mehrnoosh (Author) ; Abdekhodaei, Mohammad Jafar (Supervisor)
    The aim of this study is the fabrication of 3D porous PCL scaffolds contain core-shell fibers for cartilage tissue engineering. The novel fabrication method is co-axial wet electrospinning simultaneously. These tablets like scaffolds have superior porosity and pore sizes for cell culturing and cell-cell interaction as they have good mechanical properties for cartilage tissue engineering in comparison to 2D electrospun scaffolds. The structure of these 3D scaffolds is mimicking the ECM of cartilage. This study presents the coaxial electrospinning of PCL nanofibers encapsulated with bovine serum albumin and platelet rich plasma for demonstration of controlled release and bioactivity retention,... 

    Synthesis and Evaluation of Poly(lactic Acid)/Polyurethane Nano-composites based on Cellulose Nano-particles, with Biomedical Applications

    , M.Sc. Thesis Sharif University of Technology Mohammadian Ahrabi, Taha (Author) ; Shojaei, Akbar (Supervisor) ; Salkhi Khasraghi, Samaneh (Co-Supervisor)
    Shape memory polymers have the potential to use in the field of biomedical applications. In this research, polyurethane structures have been synthesized based on the Diol mixtures, consisting of polycaprolactane diol (PCL-diol) and poly (lactic acid) diol (PLA-diol). Aim of reasearch is about evaluating poly (lactic acid) effect in structure of the polyurethane. At the same time, cellulose nanocrystals (CNC) have been added to polymer matrix to improve properties. The synthesis of acrylated polyurethane, included the synthesis of polyurethane acrylate prepolymer. Next, this prepolymer has been cured by adding the reactive diluent and some polyol. The cured systems were investigated, finally,... 

    Effect of TiO2 morphology on in vitro bioactivity of polycaprolactone/TiO2 nanocomposites

    , Article Materials Letters ; Volume 65, Issue 15-16 , 2011 , Pages 2530-2533 ; 0167577X (ISSN) Tamjid, E ; Bagheri, R ; Vossoughi, M ; Simchi, A ; Sharif University of Technology
    TiO2 nanostructures with different morphologies (spherical, tube, leaf-like and flower-like particles) were synthesized via a facile hydrothermal process. Polycaprolactone (PCL)/10 vol.% TiO2 nanocomposites were prepared by solvent casting methods. In vitro bioactivity of the nanocomposite films was examined by immersion in the simulated body fluid (SBF) for up to 28 days. It was found that the morphology of titania nanostructures significantly influence the in vitro bioactivity of PCL/TiO 2 nanocomposites. This observation was attributed to the amount of anatase phase and the specific surface area of the TiO2 nanostructures, which provide high surface exposure to SBF  

    Supramolecular polycaprolactone nanocomposite based on functionalized hydroxyapatite

    , Article Journal of Bioactive and Compatible Polymers ; Volume 27, Issue 5 , January , 2012 , Pages 467-480 ; 08839115 (ISSN) Mehmanchi, M ; Shokrollahi, P ; Atai, M ; Omidian, H ; Bagheri, R ; Sharif University of Technology
    SAGE  2012
    Arms bearing ureido-pyrimidinone functional groups with self-association capability (through quadruple hydrogen bonds) were successfully grafted onto hydroxyapatite nanoparticles. The supramolecularly modified nanoparticles (nHApUPy) exhibited enhanced colloidal stability compared to the original hydroxyapatite nanoparticles and were uniformly dispersed in supramolecular polycaprolactone in PCL(UPy)2/HApUPy nanocomposites at different filler loadings. The combined atomic force microscopy, mechanical, and rheological analyses confirmed a high degree of compatibility of HApUPy nanoparticles with the polymer matrix. The temperature dependence of the supramolecular structure in PCL(UPy)2/HApUPy... 

    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... 

    Design of Smart Magnetic Micellar Nanocarrier Based on Modified Polycaprolactone for Targeting Delivery of Paclitaxel as Anticancer Drug

    , M.Sc. Thesis Sharif University of Technology Dastanpour, Lida (Author) ; Pourjavadi, Ali (Supervisor)
    Today, current methods are used for treatment of cancers. Patient experiences a period of hard treatment during destruction of both healthy and diseased cells. Researchers are following stimulus- response drug delivery systems that they control time and position of drug release. Meanwhile, micellar nanoparticles are important, because it can transport the hydrophobic anticancer drugs from body's physiological barriers. On the other hand, tumour tissue has low pH and high temperature as compared to health tissue. Therefore, using pH and thermosensitive polymer coating could be effective in triggered drug release. In the first study, micellar systems were synthesized which were responsive to... 

    Preparation and Characterization of Shape Memory Biocompatible Nanocomposites of Polyurethane/Carbon-magnetic Hybrid Nanoparticles

    , Ph.D. Dissertation Sharif University of Technology Salkhi Khasraghi, Samaneh (Author) ; Shojaei, Akbar (Supervisor)
    Smart bio-based shape memory polymers with high performance and fast response have the exciting potential to meet the growing need in biomedical applications. A fascinating approach in SMP categories in biomedical field is the development of noncontact activation without increasing the environmental temperature through remote triggering methods, such as magnetic triggering. Magnetically responsive SMPs have received lots of attention in the biomedical applications, especially the non-contact triggering of medical equipment and implants inside the body. In this study, the biocompatible nanocomposite based on shape memory polyurethane acrylates (SMPUAs)/ hybrid carbon-magnetic nanoparticles,... 

    Fabrication of Allograft-derived Scaffold by 3D Bioprinting for Craniofacial Defect

    , M.Sc. Thesis Sharif University of Technology Ashrafnia, Arezoo (Author) ; Mashayekhan, Shohreh (Supervisor)
    Craniofacial bone defects without scarring are a major clinical issue. These critical defects, which can be caused by infection or fracture, cannot be repaired without surgery. The main goal of skull repair is to protect vulnerable structures such as the brain, or it can be due to the improvement of jaw function and beauty. Tissue engineering can offer a new generation solution. The purpose of this study was to construct and characterise a degradable polymer/ bioceramic composite scaffold with allograft powder used in the craniofacial bone. The complexities of the extracellular matrix of humans can be simulated using 3D bioprinting.In this study, tricalcium silicate (TCS) was first... 

    Synthesis and Investigation of Properties of Biocompatible Polyurethane Acrylate Based Nanocomposites/Cellulose Nanocrystals

    , M.Sc. Thesis Sharif University of Technology Beik Mohammadi, Mahbubeh (Author) ; Shojaei, Akbar (Supervisor) ; Salkhi, Samaneh (Co-Supervisor)
    Bio-based shape memory polymers with fast-response have high potential for use in medical applications. In this study, biocompatible and biodegradable nanocomposites based on shape memory polyurethane acrylates (SMPUA)/cellulose nanocrystals (CNC), were synthesized by in-situ polymerization. CNC is a natural and renewable nanoparticle that has been considered for medical applications due to its excellent mechanical and biological properties and surface chemistry. At the first phase of this study, in order to synthesize UV-curable shape memory polyurethane acrylate, polycaprolactone diol (PCL-Diol), hexamethylene diisocyanate (HDI) and hydroxyethyl methacrylate (HEMA) were used as an reactive...