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Preparation of poly (acrylic acid) microgels by alcohol type cross-linkers and a comparison with other cross-linking methods
, Article Polymer Bulletin ; Volume 79, Issue 9 , 2022 , Pages 7775-7794 ; 01700839 (ISSN) ; Bouhendi, H ; Keshavarzi, N ; Mahmoudi, M ; Pourjavadi, A ; Ghiass, M ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
Herein, poly (acrylic acid) (PAA) microgels were synthesized via alcohol type cross-linked by a free radical precipitation polymerization approach. At the first time, 1,6-hexanediol (1–6 diol), trimethylolpropane (TMP), and pentaerythritol (PEN) were selected as multifunctional cross- linking agent to synthesize cross-linked poly(acrylic acid) microgels. Alcohol type cross-linking agents can connect the PAA chains. The cross-linking reaction takes place due to reaction between hydroxyl groups of various cross-linkers and carboxyl groups of PAA chains. All of the hydroxyl groups do not participate in the reaction with acid groups of polymer chains through the polymerization stage; therefore,...
Customizing nano-chitosan for sustainable drug delivery
, Article Journal of Controlled Release ; Volume 350 , 2022 , Pages 175-192 ; 01683659 (ISSN) ; Vahidi, O ; Moghbeli, M ; Ahmadi, S ; Asadnia, M ; Akhavan, O ; Seidi, F ; Rabiee, M ; Saeb, M. R ; Webster, T. J ; Varma, R. S ; Sharifi, E ; Zarrabi, A ; Rabiee, N ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Chitosan is a natural polymer with acceptable biocompatibility, biodegradability, and mechanical stability; hence, it has been widely appraised for drug and gene delivery applications. However, there has been no comprehensive assessment to tailor-make chitosan cross-linkers of various types and functionalities as well as complex chitosan-based semi- and full-interpenetrating networks for drug delivery systems (DDSs). Herein, various fabrication methods developed for chitosan hydrogels are deliberated, including chitosan crosslinking with and without diverse cross-linkers. Tripolyphosphate, genipin and multi-functional aldehydes, carboxylic acids, and epoxides are common cross-linkers used in...
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) ; 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
Abstract
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...
Microfluidic-assisted fiber production: Potentials, limitations, and prospects
, Article Biomicrofluidics ; Volume 16, Issue 6 , 2022 ; 19321058 (ISSN) ; Nilghaz, A ; Saadatmand, M ; Naeimirad, M ; Demello, A. J ; Sharif University of Technology
American Institute of Physics Inc
2022
Abstract
Besides the conventional fiber production methods, microfluidics has emerged as a promising approach for the engineered spinning of fibrous materials and offers excellent potential for fiber manufacturing in a controlled and straightforward manner. This method facilitates low-speed prototype synthesis of fibers for diverse applications while providing superior control over reaction conditions, efficient use of precursor solutions, reagent mixing, and process parameters. This article reviews recent advances in microfluidic technology for the fabrication of fibrous materials with different morphologies and a variety of properties aimed at various applications. First, the basic principles, as...
Developing tough terpolymer hydrogel with outstanding swelling ability by hydrophobic association cross-linking
, Article Polymer ; Volume 254 , 2022 ; 00323861 (ISSN) ; Shojaei, A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Hydrogels with remarkable hydrophilicity and tunable toughness are appealing materials to serve as superabsorbent polymers. However, chemically cross-linked hydrogels often suffer from low toughness regardless of their considerable swelling, restricting their widespread applications. In comparison, the network of physically cross-linked hydrogels can be regulated to meet both a high swelling ratio and considerable toughness. Here, we develop superabsorbent and tough hydrophobic associated hydrogels using terpolymerization of poly acrylic acid (PAA), polyacrylamide (PAM), and lauryl methacrylate (LMA) within the micelles formed by sodium dodecyl sulfate (SDS) surfactant. To this end, various...
Magnetic carboxymethyl cellulose/silk fibroin hydrogel embedded with halloysite nanotubes as a biocompatible nanobiocomposite with hyperthermia application
, Article Materials Chemistry and Physics ; Volume 287 , 2022 ; 02540584 (ISSN) ; Choopani, L ; Aghamirza Moghim Aliabadi, H ; Ganjali, F ; Kashtiaray, A ; Maleki, A ; Ahangari Cohan, R ; Salimi Bani, M ; Komijani, S ; Ahadian, M. M ; Salehpour, N ; Mahdavi, M ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
A novel and high potent magnetic nanobiocomposite was prepared based on Carboxymethyl cellulose (CMC) and epichlorohydrin (ECH) cross-linker interactions to form a three-dimensional cross-linked CMC hydrogel followed by silk fibroin (SF) and halloysite nanotubes (HNTs) modifications and further in situ Fe3O4 magnetic nanoparticles (MNPs) formation. Different analytical techniques like FT-IR, EDX, FE-SEM, XRD, TGA, and VSM were used to characterize the structure of the prepared nanobiocomposite. The spherical morphology of Fe3O4 MNPs and tubular HNTs were presented in the FE-SEM images. In biological tests, since the hemolysis percent was even less than the negative control, the CMC...
Production of uniform size cell-enclosing silk derivative vehicles through coaxial microfluidic device and horseradish crosslinking reaction
, Article European Polymer Journal ; Volume 172 , 2022 ; 00143057 (ISSN) ; Hosseini, M ; Varaa, N ; Mahmoodi, N ; Goodarzi, A ; Taghdiri Nooshabadi, V ; Hassanzadeh, S ; Arabpour, Z ; Khanmohammadi, M ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Silk fibroin (SF) as a natural biopolymer holds great potential in biomedical research because of its biocompatibility, easy processability and high strength properties. However, slow gelation time has narrowed its applications, specifically in cell-laden microparticle production due to insufficient crosslinkable moieties. This study aimed to develop cell-laden silk fibroin-phenol (SF-Ph) microparticle through co-flow microfluidic system using SF conjugated Ph moieties whereas covalent crosslinking is mediated with horseradish peroxidase (HRP) in the presence of hydrogen peroxide (H2O2). For this, the SF-Ph was synthesized through carbodiimide condensation crosslinking reaction. Aqueous...
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) ; Ramazani S. A, A ; Mehraji, S ; Eslami, H ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
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...
Piezoelectric behavior of Gamma-radiated nanocomposite hydrogel based on PVP-PEG-BaTiO3
, Article Materials Science and Engineering B: Solid-State Materials for Advanced Technology ; Volume 276 , 2022 ; 09215107 (ISSN) ; Frounchi, M ; Dadbin, S ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
This study aimed to evaluate the properties of nanocomposite hydrogel (NCH) based on poly (vinyl pyrrolidone) (PVP), poly (ethylene glycol) (PEG), and Barium titanate (BTNPs). Gamma radiation at various doses (25 kGy, 35 kGy) was employed to prepare cross-linked hydrogel. The effect of PVP concentration, PVP/PEG ratio, and BTNPs content, and irradiation dosage on gel content and swelling ratio of synthesized hydrogels were determined. The Flory-Rehner equation was employed to calculate the network parameters. The FTIR results indicate that the chemical structure was deformed through crosslinking PVP macromolecule radicals. The XRD spectra indicated the cubic phase of BTNPs particles and the...
Preparation of poly (acrylic acid) microgels by alcohol type cross-linkers and a comparison with other cross-linking methods
, Article Polymer Bulletin ; 2021 ; 01700839 (ISSN) ; Bouhendi, H ; Keshavarzi, N ; Mahmoudi, M ; Pourjavadi, A ; Ghiass, M ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
Herein, poly (acrylic acid) (PAA) microgels were synthesized via alcohol type cross-linked by a free radical precipitation polymerization approach. At the first time, 1,6-hexanediol (1–6 diol), trimethylolpropane (TMP), and pentaerythritol (PEN) were selected as multifunctional cross- linking agent to synthesize cross-linked poly(acrylic acid) microgels. Alcohol type cross-linking agents can connect the PAA chains. The cross-linking reaction takes place due to reaction between hydroxyl groups of various cross-linkers and carboxyl groups of PAA chains. All of the hydroxyl groups do not participate in the reaction with acid groups of polymer chains through the polymerization stage; therefore,...
Development and in vitro evaluation of photocurable GelMA/PEGDA hybrid hydrogel for corneal stromal cells delivery
, Article Materials Today Communications ; Volume 27 , 2021 ; 23524928 (ISSN) ; Abdekhodaie, M. J ; Mashayekhan, S ; Baradaran Rafii, A ; Kim, K ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Gelatin methacrylate (GelMA) was proved to be a promising bioink for corneal stromal cell delivery. However, GelMA has low mechanical properties which makes it difficult to be suturable and handled for clinical applicattion. In this study, three different ratios of 12.5 % GelMA and 10 % PEGDA were investigated for corneal stromal cells delivery. The mixture containing 75 % GelMA and 25 % PEGDA (75G25P) was found to have reasonable cell viability and suturing strength. Moreover, collagen nanofibers were incorporated into 75G25P hydrogel to improve the mechanical and biomimetic properties of the construct (75G25P-E). A hybrid structure was obtained by injecting the optimized bioink on the...
Efficient inductively heated shape memory polyurethane acrylate network with silane modified nanodiamond@Fe3O4 superparamagnetic nanohybrid
, Article European Polymer Journal ; Volume 159 , 2021 ; 00143057 (ISSN) ; Shojaei, A ; Janmaleki, M ; Sundararaj, U ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Multifunctional magnetic shape memory polymer (SMP) nanocomposites with high sensitivity was synthesized through inclusion of silane functionalized nanodiamond@Fe3O4 (S-NDF) hybrid nanoparticle into polycaprolactone (PCL) based polyurethane acrylate (PUA) matrix followed by in situ crosslinking of the matrix. Highly biocompatible and superparamagnetic nanodiamond(ND)@Fe3O4 nanohybrids were synthesized through in situ co-precipitation method. The morphological analysis suggested that S-NDFs filled PUAs (2 to 9 wt% loadings) well interacted with both soft and hard domains of the matrix. The base polymer and the nanocomposites presented excellent shape fixity ratio (above 97%) and shape...
Bioresorbable composite polymeric materials for tissue engineering applications
, Article International Journal of Polymeric Materials and Polymeric Biomaterials ; Volume 70, Issue 13 , 2021 , Pages 926-940 ; 00914037 (ISSN) ; Mohammadi Nasr, S ; Rabiee, N ; Bagherzadeh, M ; Ahmadi, S ; Rabiee, M ; Tahriri, M ; Tayebi, L ; Hamblin, M. R ; Sharif University of Technology
Bellwether Publishing, Ltd
2021
Abstract
This review covers the development of bioresorbable polymeric composites for applications in tissue engineering. Various commercially available bioresobable polymers are described, with emphasis on recent bioresorbable composites based on natural and synthetic polymers. Bioresorbable polymers contain hydrolyzable bonds, which are subjected to chemical degradation via either reactive hydrolysis or enzyme-catalyzed active hydrolysis. For synthetic polymers, chemical hydrolysis is the most important mode of degradation. The degradation rate can be controlled by varying the molecular weight and crystallinity. Examples of bioresorbable polymers are: polyurethane, poly(D,L)lactide,...
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...
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...
Enzymatic outside-in cross-linking enables single-step microcapsule production for high-throughput three-dimensional cell microaggregate formation
, Article Materials Today Bio ; Volume 6 , 2020 ; Salehi, S. S ; Henke, S ; Shamloo, A ; Kamperman, T ; Karperien, M ; Leijten, J ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Cell-laden hydrogel microcapsules enable the high-throughput production of cell aggregates, which are relevant for three-dimensional tissue engineering and drug screening applications. However, current microcapsule production strategies are limited by their throughput, multistep protocols, and limited amount of compatible biomaterials. We here present a single-step process for the controlled microfluidic production of single-core microcapsules using enzymatic outside-in cross-linking of tyramine-conjugated polymers. It was hypothesized that a physically, instead of the conventionally explored biochemically, controlled enzymatic cross-linking process would improve the reproducibility,...
Three-dimensional bioprinting of functional skeletal muscle tissue using gelatin methacryloyl-alginate bioinks
, Article Micromachines ; Volume 10, Issue 10 , 2019 ; 2072666X (ISSN) ; Çelebi Saltik, B ; Barros, N ; Nasiri, R ; Banton, E ; Shamloo, A ; Ashammakhi, N ; Dokmeci, M. R ; Ahadian, S ; Sharif University of Technology
MDPI AG
2019
Abstract
Skeletal muscle tissue engineering aims to fabricate tissue constructs to replace or restore diseased or injured skeletal muscle tissues in the body. Several biomaterials and microscale technologies have been used in muscle tissue engineering. However, it is still challenging to mimic the function and structure of the native muscle tissues. Three-dimensional (3D) bioprinting is a powerful tool to mimic the hierarchical structure of native tissues. Here, 3D bioprinting was used to fabricate tissue constructs using gelatin methacryloyl (GelMA)-alginate bioinks. Mechanical and rheological properties of GelMA-alginate hydrogels were characterized. C2C12 myoblasts at the density 8 × 106 cells/mL...
Enzymatically crosslinked hyaluronic acid microgels as a vehicle for sustained delivery of cationic proteins
, Article European Polymer Journal ; Volume 115 , 2019 , Pages 234-243 ; 00143057 (ISSN) ; Abdekhodaie, M. J ; Mousavi, A ; Zoetebier, B ; Dijkstra, P. J ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
In this study, a novel biodegradable hyaluronic acid (HA) based microgel were prepared via enzymatic crosslinking of tyramine conjugated HA (HA-TA) in an inverse microemulsion. HA-TA microdroplets were crosslinked within a few seconds in the presence of horseradish peroxidase (HRP) and hydrogen peroxide (H 2 O 2 ). The high water content of the polymeric network and the inherent negative charge of the HA-TA microgels provided a suitable platform for encapsulation of cationic proteins like lysozyme and TGF-β1 growth factor. The results demonstrated that lysozyme was released, after an initial burst release, in a suitable sustained manner over a period of four weeks. Both diffusion and...
Empirical modeling of mechanical properties of modified collagen/chitosan membrane by response surface methodology
, Article 24th Iranian Conference on Biomedical Engineering and 2017 2nd International Iranian Conference on Biomedical Engineering, ICBME 2017, 30 November 2017 through 1 December 2017 ; 2018 ; 9781538636091 (ISBN) ; Mashayekhan, S ; Saadatmand, M ; Khashabi, E ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
Abstract
In this study, collagen/chitosan membrane used for guided bone regeneration (GBR) was modified. Collagen and chitosan are routinely used in GBR membrane fabrication. In addition advanced platelet rich fibrin (A-PRF) is a promising substitution for fabricating membrane in dental surgery. Herein, acid soluble collagen from calf skin was extracted and characterized. The combination of A-PRF with collagen/chitosan membrane was investigated in this study. FTIR analysis revealed that chemical crosslinking using EDC/NHS was occurred. The morphology of collagen/chitosan membrane in a gradient manner of chitosan was assessed via SEM images. Response surface methodology (RSM) was used to...
A thermodynamically-consistent large deformation theory coupling photochemical reaction and electrochemistry for light-responsive gels
, Article Journal of the Mechanics and Physics of Solids ; Volume 116 , July , 2018 , Pages 239-266 ; 00225096 (ISSN) ; Zhang, H ; Naghdabadi, R ; Hu, Y ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
Gels are composed of crosslinked polymer network and solvent molecules. When the main chain network is incorporated with functional groups that can undergo photo-chemical reaction upon light irradiation, the gel becomes light-responsive. Under irradiation, the photosensitive groups may undergo photo-ionization process and generate charges that are attached to the main chain or diffuse into the solvent. The newly generated ions disturb the osmotic balance of the gel medium. As a result, water molecules and mobile ions are driven into or out of the network to compensate the osmotic imbalance, which eventually leads to macroscopic swelling or shrinking of the gel. In this work, we develop a...