scholarly journals Graphene Oxide Oxygen Content Affects Physical and Biological Properties of Scaffolds Based on Chitosan/Graphene Oxide Conjugates

Materials ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1142 ◽  
Author(s):  
Iolanda Francolini ◽  
Elena Perugini ◽  
Ilaria Silvestro ◽  
Mariangela Lopreiato ◽  
Anna Scotto d’Abusco ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Mechanical Strength ◽  
Oxygen Content ◽  
Mechanical Stability ◽  
Biological Properties ◽  
Dermal Fibroblasts ◽  
Porous Scaffolds ◽  
Low Oxygen ◽  
Interdisciplinary Field

Tissue engineering is a highly interdisciplinary field of medicine aiming at regenerating damaged tissues by combining cells with porous scaffolds materials. Scaffolds are templates for tissue regeneration and should ensure suitable cell adhesion and mechanical stability throughout the application period. Chitosan (CS) is a biocompatible polymer highly investigated for scaffold preparation but suffers from poor mechanical strength. In this study, graphene oxide (GO) was conjugated to chitosan at two weight ratios 0.3% and 1%, and the resulting conjugates were used to prepare composite scaffolds with improved mechanical strength. To study the effect of GO oxidation degree on scaffold mechanical and biological properties, GO samples at two different oxygen contents were employed. The obtained GO/CS scaffolds were highly porous and showed good swelling in water, though to a lesser extent than pure CS scaffold. In contrast, GO increased scaffold thermal stability and mechanical strength with respect to pure CS, especially when the GO at low oxygen content was used. The scaffold in vitro cytocompatibility using human primary dermal fibroblasts was also affected by the type of used GO. Specifically, the GO with less content of oxygen provided the scaffold with the best biocompatibility.

scholarly journals Suture Fiber Reinforcement of a 3D Printed Gelatin Scaffold for Its Potential Application in Soft Tissue Engineering

2021 ◽  
Vol 22 (21) ◽  
pp. 11600
Author(s):  
Dong Jin Choi ◽  
Kyoung Choi ◽  
Sang Jun Park ◽  
Young-Jin Kim ◽  
Seok Chung ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Mechanical Strength ◽  
Physical Properties ◽  
Dimensional Stability ◽  
3D Structure ◽  
Biological Properties ◽  
Dermal Fibroblasts ◽  
3D Scaffolds ◽  
3D Printed

Gelatin has excellent biological properties, but its poor physical properties are a major obstacle to its use as a biomaterial ink. These disadvantages not only worsen the printability of gelatin biomaterial ink, but also reduce the dimensional stability of its 3D scaffolds and limit its application in the tissue engineering field. Herein, biodegradable suture fibers were added into a gelatin biomaterial ink to improve the printability, mechanical strength, and dimensional stability of the 3D printed scaffolds. The suture fiber reinforced gelatin 3D scaffolds were fabricated using the thermo-responsive properties of gelatin under optimized 3D printing conditions (−10 °C cryogenic plate, 40–80 kPa pneumatic pressure, and 9 mm/s printing speed), and were crosslinked using EDC/NHS to maintain their 3D structures. Scanning electron microscopy images revealed that the morphologies of the 3D printed scaffolds maintained their 3D structure after crosslinking. The addition of 0.5% (w/v) of suture fibers increased the printing accuracy of the 3D printed scaffolds to 97%. The suture fibers also increased the mechanical strength of the 3D printed scaffolds by up to 6-fold, and the degradation rate could be controlled by the suture fiber content. In in vitro cell studies, DNA assay results showed that human dermal fibroblasts’ proliferation rate of a 3D printed scaffold containing 0.5% suture fiber was 10% higher than that of a 3D printed scaffold without suture fibers after 14 days of culture. Interestingly, the supplement of suture fibers into gelatin biomaterial ink was able to minimize the cell-mediated contraction of the cell cultured 3D scaffolds over the cell culture period. These results show that advanced biomaterial inks can be developed by supplementing biodegradable fibers to improve the poor physical properties of natural polymer-based biomaterial inks.

The Influence of Copolymer Compositions on the Physiochemical and Biological Properties of Poly (Lactic-co-Glycolic Acid) Porous Scaffolds

2010 ◽  
Vol 6 ◽  
pp. 35-44 ◽  
Author(s):  
L. Zhao ◽  
C. He ◽  
Lei Cui
Keyword(s):  
Mechanical Properties ◽  
Mechanical Strength ◽  
Glycolic Acid ◽  
High Efficiency ◽  
Dermal Fibroblast ◽  
Biological Properties ◽  
Dermal Fibroblasts ◽  
Proliferation Rate ◽  
Molar Ratio ◽  
Porous Scaffolds

To investigate the influence of initial copolymer compositions of poly (lactic-co-glycolic acid) (PLGA) on mechanical properties, degradation behavior and biological properties of the scaffolds, porous PLGA scaffolds with different initial copolymer compositions (lactide/glycolide (PLA/PGA) molar ratio: 50:50, 70:30 and 80:20) were prepared by solvent casting/particulate leaching method. Mechanical properties were measured by testing the tensile strength and degradation rate was detected by soaking the scaffolds in phosphate buffered solution at 37 °C for various time points. Human dermal fibroblasts were seeded on PLGA scaffolds with different copolymer compositions. The morphology, adhesion efficiency, proliferation rate, and total collagen contents of cells on the scaffolds were analyzed. The results showed that the ratio of PLA/PGA is one important factor which influences the degradation of scaffolds. The mechanical strength of PLGA scaffolds with the ratio of 70:30 and 80:20, was higher than that of PLGA scaffolds with the ratio of 50:50.. Compared to 70:30 and 80:20 PLGA scaffolds, 50:50 PLGA had a quicker degradation. The three PLGA scaffolds had no obvious difference for cell response and all of them had excellent cytocompatibility, indicated by their high efficiency for human dermal fibroblast adhesion, fast proliferation rate and stretched cell morphology. A large amount of extracellular matrix was secreted and after 7 days of culture, and cell nearly covered the entire surface of the scaffolds. Overall, our results indicate that the copolymer compositions of PLGA have important effect on degradation and mechanical strength, but have no obvious effect on the biological properties of the scaffolds.

scholarly journals Biomimetic reduced graphene oxide coated collagen scaffold for in situ bone regeneration

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sajad Bahrami ◽  
Nafiseh Baheiraei ◽  
Mostafa Shahrezaee
Keyword(s):  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Cranial Bone ◽  
Drying Methods ◽  
Porous Scaffolds ◽  
Alizarin Red ◽  
Reduced Graphene ◽  
Coated Collagen

AbstractA variety of bone-related diseases and injures and limitations of traditional regeneration methods require new tissue substitutes. Tissue engineering and regeneration combined with nanomedicine can provide different natural or synthetic and combined scaffolds with bone mimicking properties for implantation in the injured area. In this study, we synthesized collagen (Col) and reduced graphene oxide coated collagen (Col-rGO) scaffolds, and we evaluated their in vitro and in vivo effects on bone tissue repair. Col and Col-rGO scaffolds were synthesized by chemical crosslinking and freeze-drying methods. The surface topography, and the mechanical and chemical properties of scaffolds were characterized, showing three-dimensional (3D) porous scaffolds and successful coating of rGO on Col. The rGO coating enhanced the mechanical strength of Col-rGO scaffolds to a greater extent than Col scaffolds by 2.8 times. Furthermore, Col-rGO scaffolds confirmed that graphene addition induced no cytotoxic effects and enhanced the viability and proliferation of human bone marrow-derived mesenchymal stem cells (hBMSCs) with 3D adherence and expansion. Finally, scaffold implantation into rabbit cranial bone defects for 12 weeks showed increased bone formation, confirmed by Hematoxylin–Eosin (H&E) and alizarin red staining. Overall, the study showed that rGO coating improves Col scaffold properties and could be a promising implant for bone injuries.

scholarly journals Gradient Chitosan Hydrogels Modified with Graphene Derivatives and Hydroxyapatite: Physiochemical Properties and Initial Cytocompatibility Evaluation

2020 ◽  
Vol 21 (14) ◽  
pp. 4888
Author(s):  
Karolina Kosowska ◽  
Patrycja Domalik-Pyzik ◽  
Małgorzata Sekuła-Stryjewska ◽  
Sylwia Noga ◽  
Joanna Jagiełło ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Photoelectron Spectroscopy ◽  
Mechanical Analysis ◽  
Biological Properties ◽  
Human Umbilical Cord ◽  
Tissue Engineering Scaffolds ◽  
X Ray ◽  
Chitosan Matrix ◽  
Graphene Derivatives

In this study, we investigated preparation of gradient chitosan-matrix hydrogels through a novel freezing–gelling–thawing method. The influence of three types of graphene family materials (GFM), i.e., graphene oxide (GO), reduced graphene oxide (rGO), and poly(ethylene glycol) grafted graphene oxide (GO-PEG), as well as hydroxyapatite (HAp) on the physicochemical and biological properties of the composite hydrogels was examined in view of their potential applicability as tissue engineering scaffolds. The substrates and the hydrogel samples were thoroughly characterized by X-ray photoelectron spectroscopy, X-ray diffractometry, infrared spectroscopy, digital and scanning electron microscopy, rheological and mechanical analysis, in vitro chemical stability and bioactivity assays, as well as initial cytocompatibility evaluation with human umbilical cord Wharton’s jelly mesenchymal stem cells (hUC-MSCs). We followed the green-chemistry approach and avoided toxic cross-linking agents, using instead specific interactions of our polymer matrix with tannic acid, non-toxic physical cross-linker, and graphene derivatives. It was shown that the most promising are the gradient hydrogels modified with GO-PEG and HAp.

scholarly journals Enamel Anti-Demineralization Effect of Orthodontic Adhesive Containing Bioactive Glass and Graphene Oxide: an in-Vitro Study

2018 ◽  
Author(s):  
Seung-Min Lee ◽  
Kyung-Hyeon Yoo ◽  
Seog-Young Yoon ◽  
In-Ryoung Kim ◽  
Bong-Soo Park ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Graphene Oxide ◽  
Cell Viability ◽  
Bioactive Glass ◽  
In Vitro Study ◽  
Biological Properties ◽  
Low Viscosity ◽  
Adhesive Remnant Index ◽  
Base Solution

White spot lesions (WSLs), a side effect of orthodontic treatment, can result in reversible and unaesthetic results. Graphene oxide (GO) with a bioactive glass (BAG) mixture(BAG@GO) was added to Low Viscosity Transbond XT(LV) in a ratio of 1, 3, 5%. The composite’s characterization and its physical and biological properties were verified with scanning electron microscopy(SEM) and X-ray diffraction(XRD); its microhardness, shear bond stress (SBS), cell viability, and adhesive remnant index (ARI) were also assessed. Efficiency in reducing WSL was evaluated using antibacterial activity of S. mutans. Anti-demineralization was analyzed using a cycle of the acid-base solution. Adhesives with 3 or 5 wt.% of BAG@GO showed significant increase in microhardness compared with LV. The sample and LV groups showed no significant differences in SBS or ARI. The cell viability test confirmed that none of the sample groups showed higher toxicity compared to the LV group. Antibacterial activity was higher in the 48-hour group than in the 24-hour group; the 48-hour test showed that BAG@GO had a high antibacterial effect, which was more pronounced in 5 wt.% of BAG@GO. Anti-demineralization effect was higher in the BAG@GO-group than in the LV-group; the higher the BAG@GO concentration, the higher the anti-demineralization effect.

scholarly journals Human Mesenchymal Stromal Cell-Derived Exosomes Promote In Vitro Wound Healing by Modulating the Biological Properties of Skin Keratinocytes and Fibroblasts and Stimulating Angiogenesis

2021 ◽  
Vol 22 (12) ◽  
pp. 6239
Author(s):  
Raluca Tutuianu ◽  
Ana-Maria Rosca ◽  
Daniela Madalina Iacomi ◽  
Maya Simionescu ◽  
Irina Titorencu
Keyword(s):  
Wound Healing ◽  
Smooth Muscle Actin ◽  
Cell Types ◽  
Biological Properties ◽  
Dermal Fibroblasts ◽  
Type I ◽  
Accelerate Wound Healing ◽  
Skin Keratinocytes ◽  
And Migration

Bone marrow-derived mesenchymal stromal cells (MSCs) are major players in regenerative therapies for wound healing via their paracrine activity, mediated partially by exosomes. Our purpose was to test if MSC-derived exosomes could accelerate wound healing by enhancing the biological properties of the main cell types involved in the key phases of this process. Thus, the effects of exosomes on (i) macrophage activation, (ii) angiogenesis, (iii) keratinocytes and dermal fibroblasts proliferation and migration, and (iv) the capacity of myofibroblasts to regulate the turnover of the extracellular matrix were evaluated. The results showed that, although exosomes did not exhibit anti-inflammatory properties, they stimulated angiogenesis. Exposure of keratinocytes and dermal (myo)fibroblasts to exosomes enhanced their proliferation and migratory capacity. Additionally, exosomes prevented the upregulation of gene expression for type I and III collagen, α-smooth muscle actin, and MMP2 and 14, and they increased MMP13 expression during the fibroblast–myofibroblast transition. The regenerative properties of exosomes were validated using a wound healing skin organotypic model, which exhibited full re-epithelialization upon exosomes exposure. In summary, these data indicate that exosomes enhance the biological properties of keratinocytes, fibroblasts, and endothelial cells, thus providing a reliable therapeutic tool for skin regeneration.

scholarly journals Biodegradable Chitosan-graft-Poly(l-lactide) Copolymers For Bone Tissue Engineering

Polymers ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 316 ◽  
Author(s):  
Maria Kaliva ◽  
Anthie Georgopoulou ◽  
Dimitrios A. Dragatogiannis ◽  
Costas A. Charitidis ◽  
Maria Chatzinikolaidou ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Cell Culture ◽  
Mechanical Stability ◽  
Young Modulus ◽  
Biological Properties ◽  
Design And Synthesis ◽  
Copolymer Films ◽  
Strong Adhesion ◽  
Lactide Copolymers

The design and synthesis of new biomaterials with adjustable physicochemical and biological properties for tissue engineering applications have attracted great interest. In this work, chitosan-graft-poly(l-lactide) (CS-g-PLLA) copolymers were prepared by chemically binding poly(l-lactide) (PLLA) chains along chitosan (CS) via the “grafting to” approach to obtain hybrid biomaterials that present enhanced mechanical stability, due to the presence of PLLA, and high bioactivity, conferred by CS. Two graft copolymers were prepared, CS-g-PLLA(80/20) and CS-g-PLLA(50/50), containing 82 wt % and 55 wt % CS, respectively. Degradation studies of compressed discs of the copolymers showed that the degradation rate increased with the CS content of the copolymer. Nanomechanical studies in the dry state indicated that the copolymer with the higher CS content had larger Young modulus, reduced modulus and hardness values, whereas the moduli and hardness decreased rapidly following immersion of the copolymer discs in alpha-MEM cell culture medium for 24 h. Finally, the bioactivity of the hybrid copolymers was evaluated in the adhesion and growth of MC3T3-E1 pre-osteoblastic cells. In vitro studies showed that MC3T3-E1 cells exhibited strong adhesion on both CS-g-PLLA graft copolymer films from the first day in cell culture, whereas the copolymer with the higher PLLA content, CS-g-PLLA(50/50), supported higher cell growth.

scholarly journals Development of Arabinoxylan-Reinforced Apple Pectin/Graphene Oxide/Nano-Hydroxyapatite Based Nanocomposite Scaffolds with Controlled Release of Drug for Bone Tissue Engineering: In-Vitro Evaluation of Biocompatibility and Cytotoxicity against MC3T3-E1

Coatings ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1120
Author(s):  
Wafa Shamsan Al-Arjan ◽  
Muhammad Umar Aslam Khan ◽  
Samina Nazir ◽  
Saiful Izwan Abd Razak ◽  
Mohammed Rafiq Abdul Kadir
Keyword(s):  
Tissue Engineering ◽  
Graphene Oxide ◽  
Bone Tissue Engineering ◽  
Pore Size ◽  
Bone Tissue ◽  
Critical Role ◽  
Testing Machine ◽  
Porous Scaffolds ◽  
Nanocomposite Scaffolds

Fabrication of reinforced scaffolds to repair and regenerate defected bone is still a major challenge. Bone tissue engineering is an advanced medical strategy to restore or regenerate damaged bone. The excellent biocompatibility and osteogenesis behavior of porous scaffolds play a critical role in bone regeneration. In current studies, we synthesized polymeric nanocomposite material through free-radical polymerization to fabricate porous nanocomposite scaffolds by freeze drying. Functional group, surface morphology, porosity, pore size, and mechanical strength were examined through Fourier Transform Infrared Spectroscopy (FTIR), Single-Electron Microscopy (SEM), Brunauer-Emmet-Teller (BET), and Universal Testing Machine (UTM), respectively. These nanocomposites exhibit enhanced compressive strength (from 4.1 to 16.90 MPa), Young’s modulus (from 13.27 to 29.65 MPa) with well appropriate porosity and pore size (from 63.72 ± 1.9 to 45.75 ± 6.7 µm), and a foam-like morphology. The increasing amount of graphene oxide (GO) regulates the porosity and mechanical behavior of the nanocomposite scaffolds. The loading and sustained release of silver-sulfadiazine was observed to be 90.6% after 260 min. The in-vitro analysis was performed using mouse pre-osteoblast (MC3T3-E1) cell lines. The developed nanocomposite scaffolds exhibited excellent biocompatibility. Based on the results, we propose these novel nanocomposites can serve as potential future biomaterials to repair defected bone with the load-bearing application, and in bone tissue engineering.

scholarly journals Synergistic effects of retinoic acid and graphene oxide on the physicochemical and in-vitro properties of electrospun polyurethane scaffolds for bone tissue engineering

e-Polymers ◽  
2017 ◽  
Vol 17 (5) ◽  
pp. 363-371 ◽  
Author(s):  
Mohammad Mahdi Safikhani ◽  
Ali Zamanian ◽  
Farnaz Ghorbani
Keyword(s):  
Tissue Engineering ◽  
Graphene Oxide ◽  
Retinoic Acid ◽  
Synergistic Effects ◽  
Biological Properties ◽  
Electrospinning Process ◽  
Hard Tissue ◽  
Tissue Engineering Scaffolds ◽  
Sem Micrographs

AbstractTissue engineering scaffolds simulate extracellular matrixes (ECMs) to promote healing processes of damaged tissues. In this investigation, ECM were simulated by retinoic acid-loaded polyurethane-graphene oxide nanofibers to regenerate bone defects. Scanning electron microscopy (SEM) micrographs, Fourier transform infrared (FTIR) spectrum and X-ray diffraction (XRD) patterns proved the synthesis of graphene oxide (GO) nanosheets. SEM micrographs of nanofibers demonstrated through the formation of homogeneous and bead free fibrous scaffolds that the diameter of fibers were reduced by decreasing the applied voltage in an electrospinning process and the addition of GO. According to the results, the addition of GO to the polyurethane (PU) solution led to an increase in mechanical strength which is the most important parameter in the hard tissue repair. The GO-containing scaffolds showed an increased wettability, swelling, biodegradation and drug release level. Release behavior in nanocomposite scaffolds followed the swelling and biodegradation mechanisms, so osteogenic expression was possible by incorporating retinoic acid (RA) in PU-GO nanofibrous scaffolds. Biological evaluations demonstrated that composite scaffolds are biocompatible and support cellular attachment in which RA-loaded samples represented better cellular spreading. In brief, nanocomposite fibers showed desired that the physicochemical, mechanical and biological properties and synergic effects of GO and RA in osteogenic activity of MG-63 cells produced favorable constructs for hard tissue engineering applications.

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