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scaffolds--biology
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Mechanical modeling of silk fibroin/TiO2 and silk fibroin/fluoridated TiO2 nanocomposite scaffolds for bone tissue engineering
, Article Iranian Polymer Journal (English Edition) ; Volume 29, Issue 3 , February , 2020 , Pages 219-224 ; Madaah Hosseini, H. R ; Samadikuchaksaraei, A ; Sharif University of Technology
Springer
2020
Abstract
Biocompatible and biodegradable three-dimensional scaffolds are commonly porous which serve to provide suitable microenvironments for mechanical supporting and optimal cell growth. Silk fibroin (SF) is a natural and biomedical polymer with appropriate and improvable mechanical properties. Making a composite with a bioceramicas reinforcement is a general strategy to prepare a scaffold for hard tissue engineering applications. In the present study, SF was separately combined with titanium dioxide (TiO2) and fluoridated titanium dioxide nanoparticles (TiO2-F) as bioceramic reinforcements for bone tissue engineering purposes. At the first step, SF was extracted from Bombyx mori cocoons. Then,...
Manipulating failure mechanism of rapid prototyped scaffolds by changing nodal connectivity and geometry of the pores
, Article Journal of Biomechanics ; Volume 45, Issue 16 , 2012 , Pages 2866-2875 ; 00219290 (ISSN) ; Bagheri, R ; Zehtab Yazdi, A ; Sharif University of Technology
2012
Abstract
The performance of cellular solids in biomedical applications relies strongly on a detailed understanding of the effects of pore topology on mechanical properties. This study aims at characterizing the failure mechanism of scaffolds based on nodal connectivity (number of struts that meet in joints) and geometry of the pores. Plastic models of scaffolds having the same relative density but different cubic and trigonal unit cells were designed and then fabricated via three dimensional (3-D) printing. Unit cells were repeated in different arrangements in 3-D space. An in-situ imaging technique was utilized to study the progressive deformation of the scaffold models. Different nodal...
Magnetic nanocomposites for biomedical applications
, Article Advances in Colloid and Interface Science ; Volume 308 , 2022 ; 00018686 (ISSN) ; Ghovvati, M ; Rabiee, N ; Ahmadi, S ; Abbariki, N ; Sojdeh, S ; Ojaghi, A ; Bagherzadeh, M ; Akhavan, O ; Sharifi, E ; Rabiee, M ; Saeb, M. R ; Bolouri, K ; Webster, T. J ; Zare, E. N ; Zarrabi, A ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Tissue engineering and regenerative medicine have solved numerous problems related to the repair and regeneration of damaged organs and tissues arising from aging, illnesses, and injuries. Nanotechnology has further aided tissue regeneration science and has provided outstanding opportunities to help disease diagnosis as well as treat damaged tissues. Based on the most recent findings, magnetic nanostructures (MNSs), in particular, have emerged as promising materials for detecting, directing, and supporting tissue regeneration. There have been many reports concerning the role of these nano-building blocks in the regeneration of both soft and hard tissues, but the subject has not been...
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) ; Mohammadi, M. R ; Sharif University of Technology
2013
Abstract
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...
Interface engineering of perovskite solar cell using a reduced-graphene scaffold
, Article Journal of Physical Chemistry C ; Volume 120, Issue 35 , Volume 120, Issue 35 , 2016 , Pages 19531-19536 ; 19327447 (ISSN) ; Tavakoli, R ; Hasanzadeh, S ; Mirfasih, M. H ; Sharif University of Technology
American Chemical Society
Abstract
Interface engineering of solar cell device is a prominent strategy to improve the device performance. Herein, we synthesize reduced-graphene scaffold (rGS) by using a new and simple chemical approach. In this regard, we synthesize a hollow structure of graphene and then fabricate a three-dimensional scaffold of graphene with a superior surface area using electrophoretic process. We employ this scaffold as an interface layer between the electron transfer and absorber layers in perovskite solar cell. The characterization tests and photovoltaic results show that rGS improves the carrier transportation, yielding a 27% improvement in device performance as compared to conventional device. Finally,...
In situ synthesized TiO2-polyurethane nanocomposite for bypass graft application: In vitro endothelialization and degradation
, Article Materials Science and Engineering C ; Volume 114 , May , 2020 ; Bagheri, R ; Pourjavadi, A ; Ghanbari, H ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
The in vitro endothelial response of human umbilical vein endothelial cells was investigated on a poly (caprolactone)-based polyurethane surface vs an in situ TiO2-polyurethane nanocomposite surface, which has been produced as scaffolds for artificial vascular graft. The in situ synthesis of TiO2 nanoparticles in polyurethane provided surface properties that facilitated cellular adhesion, cell sensing, cell probing and especially cell migration. Cells on the nanocomposite surface have elongated morphology and were able to produce more extracellular matrix. All of these advantages led to an increase in the rate of endothelialization of the nanocomposite scaffold surface vs pure polyurethane....
In-situ crosslinking of electrospun gelatin-carbodiimide nanofibers: fabrication, characterization, and modeling of solution parameters
, Article Chemical Engineering Communications ; 2020 ; Alemzadeh, I ; Vossoughi, M ; Shamloo, A ; Sharif University of Technology
Taylor and Francis Ltd
2020
Abstract
This work has focused on in-situ crosslinking of gelatin (G) to produce electrospun scaffold with improved fiber morphology retention and mechanical properties. As per this approach, we prepared G nanofibers through mixing G, 1-ethyl-3-(3 dimethylaminopropyl) carbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) in the new solvent system. Response surface methodology (RSM) was employed to study the influence of solution parameters on fiber diameter. The morphological structure was examined, and the appropriate level of setting to obtain smooth fibers with a favorable diameter was reported. Results revealed using EDC/NHS for in-situ crosslinking improves the mechanical properties...
In-situ crosslinking of electrospun gelatin-carbodiimide nanofibers: fabrication, characterization, and modeling of solution parameters
, Article Chemical Engineering Communications ; Volume 208, Issue 7 , 2021 , Pages 976-992 ; 00986445 (ISSN) ; Alemzadeh, I ; Vossoughi, M ; Shamloo, A ; Sharif University of Technology
Taylor and Francis Ltd
2021
Abstract
This work has focused on in-situ crosslinking of gelatin (G) to produce electrospun scaffold with improved fiber morphology retention and mechanical properties. As per this approach, we prepared G nanofibers through mixing G, 1-ethyl-3-(3 dimethylaminopropyl) carbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) in the new solvent system. Response surface methodology (RSM) was employed to study the influence of solution parameters on fiber diameter. The morphological structure was examined, and the appropriate level of setting to obtain smooth fibers with a favorable diameter was reported. Results revealed using EDC/NHS for in-situ crosslinking improves the mechanical properties...
Influence of Fe3O4 nanoparticles in hydroxyapatite scaffolds on proliferation of primary human fibroblast cells
, Article Journal of Materials Engineering and Performance ; 2016 , Pages 1-9 ; 10599495 (ISSN) ; Aghaie, E ; Nadernezhad, A ; Zargarzadeh, M ; Khakzad, A ; Shakeri, M. S ; Beygi Khosrowshahi, Y ; Siadati, M. H ; Sharif University of Technology
Springer New York LLC
2016
Abstract
Modern techniques for expanding stem cells play a substantial role in tissue engineering: the raw material that facilitates regeneration of damaged tissues and treats diseases. The environmental conditions and bioprocessing methods are the primary determinants of the rate of cultured stem cell proliferation. Bioceramic scaffolds made of calcium phosphate are effective substrates for optimal cell proliferation. The present study investigates the effects of two bioceramic scaffolds on proliferating cells in culture media. One scaffold was made of hydroxyapatite and the other was a mixture of hydroxyapatite and ferromagnetic material (Fe3O4 nanoparticles). Disk-shaped (10 mm × 2 mm) samples of...
Hybrid silk fibroin–gelatin nanofibrous sheet for drug delivery and regenerative medicine: In-vitro characterization and controlled release of simvastatin/protein
, Article Polymers for Advanced Technologies ; 2020 ; Alemzadeh, I ; Vossoughi, M ; Sharif University of Technology
John Wiley and Sons Ltd
2020
Abstract
Blend drug-loading method in electrospun scaffolds has gained much attention as a cost-effective and simple delivery system in regenerative medicine. However, it has some drawbacks, such as the burst release of encapsulated drugs and denaturing active agents in harsh organic solvents. In this study, a new silk fibroin-gelatin (SF–G) fibrous sheet has been introduced as an engineered scaffold and a straightforward drug delivery system for skin tissue engineering applications. The hybrid sheets have been prepared via co-electrospinning and in-situ crosslinking methods without corrosive solvents and toxic crosslinking agents. To evaluate the proposed scaffold as a controlled release system, the...
Hybrid silk fibroin–gelatin nanofibrous sheet for drug delivery and regenerative medicine: In-vitro characterization and controlled release of simvastatin/protein
, Article Polymers for Advanced Technologies ; Volume 32, Issue 3 , 2021 , Pages 1333-1344 ; 10427147 (ISSN) ; Alemzadeh, I ; Vossoughi, M ; Sharif University of Technology
John Wiley and Sons Ltd
2021
Abstract
Blend drug-loading method in electrospun scaffolds has gained much attention as a cost-effective and simple delivery system in regenerative medicine. However, it has some drawbacks, such as the burst release of encapsulated drugs and denaturing active agents in harsh organic solvents. In this study, a new silk fibroin-gelatin (SF–G) fibrous sheet has been introduced as an engineered scaffold and a straightforward drug delivery system for skin tissue engineering applications. The hybrid sheets have been prepared via co-electrospinning and in-situ crosslinking methods without corrosive solvents and toxic crosslinking agents. To evaluate the proposed scaffold as a controlled release system, the...
Human olfactory mucosa stem cells delivery using a collagen hydrogel: As a potential candidate for bone tissue engineering
, Article Materials ; Volume 14, Issue 14 , 2021 ; 19961944 (ISSN) ; Milan, P. B ; Saadatmand, M ; Bagher, Z ; Gholipourmalekabadi, M ; Alizadeh, R ; Hivechi, A ; Arabpour, Z ; Hamidi, M ; Delattre, C ; Sharif University of Technology
MDPI AG
2021
Abstract
For bone tissue engineering, stem cell‐based therapy has become a promising option. Re-cently, cell transplantation supported by polymeric carriers has been increasingly evaluated. Herein, we encapsulated human olfactory ectomesenchymal stem cells (OE‐MSC) in the collagen hydrogel system, and their osteogenic potential was assessed in vitro and in vivo conditions. Col-lagen type I was composed of four different concentrations of (4 mg/mL, 5 mg/mL, 6 mg/mL, 7 mg/mL). SDS‐Page, FTIR, rheologic test, resazurin assay, live/dead assay, and SEM were used to characterize collagen hydrogels. OE‐MSCs encapsulated in the optimum concentration of collagen hydrogel and transplanted in rat calvarial...
Green polymer nanocomposites for skin tissue engineering
, Article ACS Applied Bio Materials ; 2022 ; 25766422 (ISSN) ; 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
Abstract
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...
Graphene scaffolds in progressive nanotechnology/stem cell-based tissue engineering of the nervous system
, Article Journal of Materials Chemistry B ; Volume 4, Issue 19 , 2016 , Pages 3169-3190 ; 20507518 (ISSN) ; Sharif University of Technology
Royal Society of Chemistry
2016
Abstract
Although graphene/stem cell-based tissue engineering has recently emerged and has promisingly and progressively been utilized for developing one of the most effective regenerative nanomedicines, it suffers from low differentiation efficiency, low hybridization after transplantation and lack of appropriate scaffolds required in implantations without any degrading in functionality of the cells. In fact, recent studies have demonstrated that the unique properties of graphene can successfully resolve all of these challenges. Among various stem cells, neural stem cells (NSCs) and their neural differentiation on graphene have attracted a lot of interest, because graphene-based neuronal tissue...
Glucose cross-linked hydrogels conjugate HA nanorods as bone scaffolds: Green synthesis, characterization and in vitro studies
, Article Materials Chemistry and Physics ; Volume 242 , 2020 ; Shafiei, N ; Mohandes, F ; Dolatyar, B ; Zandi, N ; Zeynali, B ; Simchi, A ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
In the expanding field of tissue engineering (TE), improvement of biodegradability and osteoconductivity of biomaterials are required. The use of non-toxic reagents during manufacturing processes is also necessary to decrease toxicity and increase cell viability in vivo. Herein, we present a novel approach to prepare hydroxyapatite (HA) nanorods from sea bio-wastes through a green and eco-friendly wet-chemical processing for bone TE. Highly porous natural polymer-ceramic nanocomposites made of HA, gelatin (Ge) and carboxymethyl cellulose (CMC) hydrogels are then introduced. It was found that cross-linking of the hydrogel matrix by glucose as a green reagent affected all characteristics of...
Freeze-gelled alginate/gelatin scaffolds for wound healing applications: An in vitro, in vivo study
, Article Materials Science and Engineering C ; Volume 113 , 2020 ; Shamloo, A ; Kamali, A ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
In this study, fabrication of a three-dimensional porous scaffold was performed using freeze gelation method. Recently, fabrication of scaffolds using polymer blends has become common for many tissue engineering applications due to their unique tunable properties. In this work, we fabricated alginate-gelatin porous hydrogels for wound healing application using a new method based on some modifications to the freeze-gelation method. Alginate and gelatin were mixed in three different ratios and the resulting solutions underwent freeze gelation to obtain 3D porous matrices. We analyzed the samples using different characterization tests. The scanning electron microscopy (SEM) results indicated...
Fabrication of PLA/PEG/MWCNT electrospun nanofibrous scaffolds for anticancer drug delivery
, Article Journal of Applied Polymer Science ; Volume 132, Issue 3 , August , 2015 ; 00218995 (ISSN) ; Rad, L. R ; Irani, M ; Haririan, I ; Sharif University of Technology
John Wiley and Sons Inc
2015
Abstract
In the present study, polylactic acid (PLA)/polyethylene glycol (PEG)/multiwalled carbon nanotube (MWCNT) electrospun nanofibrous scaffolds were prepared via electrospinning process and their applications for the anticancer drug delivery system were investigated. A response surface methodology based on Box-Behnken design (BBD) was used to evaluate the effect of key parameters of electrospinning process including solution concentration, feeding rate, tip-collector distance (TCD) and applied voltage on the morphology of PLA/PEG/MWCNT nanofibrous scaffolds. In optimum conditions (concentration of 8.15%, feeding rate of 0.2 mL/h, voltage of 18.50 kV and TCD of 13.0 cm), the minimum experimental...
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) ; Alemzadeh, I ; Tamjid, E ; Khafaji, M ; Vossoughi, M ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
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...
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) ; Sadrnezhaad, S. K ; Shokrgozar, M. A ; Bonakdar, S ; Sharif University of Technology
Springer
2012
Abstract
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...
Fabrication of a novel 3D scaffold for cartilage tissue repair: In-vitro and in-vivo study
, Article Materials Science and Engineering C ; Volume 128 , 2021 ; 09284931 (ISSN) ; Shamloo, A ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Self-repairing is not an advanced ability of articular cartilage. Tissue engineering has provided a novel way for reconstructing cartilage using natural polymers because of their biocompatibility and bio-functionality. The purpose of cartilage tissue engineering is to design a scaffold with proper pore structure and similar biological and mechanical properties to the native tissue. In this study, porous scaffolds prepared from gelatin, chitosan and silk fibroin were blended with varying ratios. Between the blends of chitosan (C), gelatin (G) and silk fibroin (S), the scaffold with the weight per volume ratio of 2:2:3 (w/v) showed the most favorable and higher certain properties than the...