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1.
Nanofibrous biocomposite scaffolds of poly(vinyl alcohol) (PVA) and graphene oxide (GO) were prepared by using electrospinning method. The microstructure, crystallinity, and morphology of the scaffolds were characterized through X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The mechanical properties were investigated by tensile testing. Moreover, Mouse Osteoblastic Cells (MC3T3‐E1) attachment and proliferation on the nanofibrous scaffolds were investigated by MTT [3‐(4,5‐dimeth‐ylthiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide] assay, SEM observation and fluorescence staining. XRD and FTIR results verify the presence of GO in the scaffolds. SEM images show the three‐dimensional porous fibrous morphology, and the average diameter of the composite fibers decreases with increasing the content of GO. The mechanical properties of the scaffolds are altered by changing the content of GO as well. The tensile strength and elasticity modulus increase when the content of GO is lower than 1 wt %, but decrease when GO is up to 3 and 5 wt %. MC3T3‐E1 cells attach and grow on the surfaces of the scaffolds, and the adding of GO do not affect the cells' viability. Also, MC3T3‐E1 cells are likely to spread on the PVA/GO composite scaffolds. Above all, these unique features of the PVA/GO nanofibrous scaffolds prepared by electrospinning would open up a wide variety of future applications in bone tissue engineering and drug delivery systems. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

2.
Porous ceramic scaffolds are synthetic implants, which support cell migration and establish sufficient extracellular matrix (ECM) and cell-cell interactions to heal bone defects. Hydroxyapatite (HA) scaffolds is one of the most suitable synthetic scaffolds for hard tissue replacement due to their bioactivity, biocompatibility and biomimetic features. However, the major disadvantages of HA is poor mechanical properties as well as low degradability rate and apatite formation ability. In this study, we developed a new method to improve the bioactivity, biodegradability and mechanical properties of natural hydroxyfluorapatite (HFA) by applying two-step coating process including ceramic and polymer coats. The structure, morphology and bioactivity potential of the modified and unmodified nanocomposite scaffolds were evaluated using transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and energy dispersive spectroscopy (EDS). The scaffold with optimized mechanical properties was HFA-30?wt%HT (HT stands for hardystonite) with a total porosity and pore size of 89?±?1 and 900–1000?µm, respectively. The compressive modulus and strength of HFA (porosity ~ 93?±?1) were improved from 108.81?±?11.12–251.45?±?12.2?MPa and 0.46?±?0.1–1.7?±?0.3?MPa in HFA-30?wt%HT sample, respectively. After applying poly(ε-caprolactone fumarate) (PCLF) polymer coating, the compressive strength and modules increased to 2.8?±?0.15 and 426.1?±?15.14?MPa, respectively. The apatite formation ability of scaffolds was investigated using simulated body fluid (SBF). The results showed that applying the hardystonite coating improve the apatite formation ability; however, the release of ions increased the pH. Whereas, modified scaffolds with PCLF could control the release of ions and improve the apatite formation ability as well.  相似文献   

3.
To improve the mechanical properties of polyvinyl alcohol (PVA) fibers, a series of PVA fibers were prepared via dry-wet spinning with cross-linking of boric acid (BA) (PVA/BA fibers), and using the mixed solvent of dimethyl sulfoxide and water. Moreover, the final PVA/BA fibers were characterized by Fourier transform infrared spectra (FTIR), scanning electron microscopy (SEM), differential scanning calorimetery (DSC), thermogravimetric analyzer (TGA), powder X-ray diffraction (XRD) and yarn strength tester. Furthermore, with the increasing of BA content, FTIR analysis showed that the degree of crosslinking of BA with PVA increased. SEM images of final PVA/BA fibers presented smooth surfaces, and the diameters decreased firstly and then increased. DSC, TGA, and XRD analysis indicated that the melting temperatures, thermal properties and crystallinities first increased and then decreased with the increasing of BA content. In addition, mechanical properties measurements illustrated that the cross-linking existed at an optimal BA content of 0.3 wt%, and PVA/BA-0.3 fiber had the highest tensile strength and Young's modulus of 13.1 ± 0.4 and 360.2 ± 10.4 cN/dtex, respectively.  相似文献   

4.
Chitosan (CS) bicomponent nanofibers with an average diameter controlled from 100 to 50 nm were successfully prepared by electrospinning of CS and poly(vinyl alcohol) (PVA) blend solution. Finer fibers and more efficient fiber formations were observed with increased PVA contents. On this contribution, a uniform and ultrafine nanofibrous CS bicomponent mats filled with hydroxyapatite (HA) nanoparticles were successfully electrospun in a well devised condition. An increase in the contents of HA nanoparticles caused the conductivity of the blend solution to increase from 1.06 mS/cm (0 wt % HA) to 2.27 mS/cm (0.5 wt % HA), 2.35 mS/cm (1.0 wt % HA), respectively, and the average diameter of the composite fibers to decrease from 59 ± 10 nm(0 wt % HA) to 49 ± 10 nm (0.5 wt % HA), 46 ± 10 nm (1.0 wt % HA), respectively. SEM images showed that some particles had filled in the nanofibers whereas the others had dispersed on the surface of fibers, and EDXA results indicated that both the nanoparticles filled in the nanofibers and those adhered to the fibers were HA particles. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

5.
以壳聚糖(CS)为基材,使用静电纺丝的方法制备了搭载壳寡糖(CHOS)的CS/聚乙烯醇(PVA)/CHOS纳米纤维膜,并对纳米纤维膜的微观形貌、结构、抑菌性、亲水性以及溶解性能进行了研究。研究发现:CS/PVA/CHOS纳米纤维膜具备均匀密致的微观形貌;FT-IR测试表明,CHOS以物理混合的形式分散在CS/PVA/CHOS纳米纤维膜中;XRD测试表明,CHOS的加入改变了纳米纤维膜的结晶性,促进了各组分之间的相容性;水接触角测试表明纳米纤维膜具备良好的亲水性,在m(CS):m(PVA):m(CHOS)=20:80:10时,CS/PVA/CHOS纳米纤维膜的接触角相比于m(CS):m(PVA)=20:80的CS/PVA纳米纤维膜由59.8°下降到37.5°;抑菌性能和溶解性能测试表明,m(CS):m(PVA):m(CHOS)=20:80:10时的CS/PVA/CHOS纳米纤维膜相比于未搭载CHOS的CS/PVA纳米纤维膜,抑菌性提升了38.9%,溶解率提升了38.6%。  相似文献   

6.
Aloe vera (AV) is one of the medicinal herbs with a well-established spectrum of wound healing, antimicrobial and anti-inflammatory property. AV-mediated therapeutics present significant tissue regenerative activity by modulating the inflammatory and proliferative phases of wound healing. The purpose of the present work was to combine the biological properties of AV and the advantages of electrospun meshes to prepare a potent transdermal biomaterial. The polycaprolactone (PCL) containing 5 and 10 wt % of lyophilized powder of AV was studied for electrospinning into nanoscale fiber mats and compared with PCL/Collagen blend for dermal substitutes. SEM revealed the average diameters of PCL, PCL-AV 5 %, PCL-AV 10 % and PCL/Collagen nanofiber scaffolds in the range of 519 ± 28, 264 ± 46, 215 ± 63 and 249 ± 52 nm, respectively. PCL-AV 10 % nanofiber scaffolds showed finer fiber morphology with improved hydrophilic properties and higher tensile strength of 6.28 MPa with a Young’s modulus of 16.11 MPa desirable for skin tissue engineering. The nanofibers were then used to investigate differences in biological responses in terms of proliferation and cell morphology of mice dermal fibroblasts. It was found that PCL-AV 10 % nanofibrous matrix favored cell proliferation compared to other scaffolds which almost increased linearly by (p ≤ 0.01) 17.79 % and (p ≤ 0.01) 21.28 % compared to PCL on sixth and ninth day. CMFDA dye expression, secretion of collagen and F-actin expression were significantly increased in PCL-AV 10 % scaffolds compared to other nanofibrous scaffolds. The obtained results proved that the PCL-AV 10 % nanofibrous scaffold is a potential biomaterial for skin tissue regeneration.  相似文献   

7.
Chitosan/hydroxyapatite (CS/HA) bone repair scaffolds crosslinked by glutaraldehyde (GA) were prepared. Characterization of morphology, structure, mechanical property, and porosity of scaffolds were evaluated. The influences of CS viscosity, HA content, and crosslinking degree on properties of scaffolds were discussed. SEM images showed that CS/HA scaffolds were porous with short rod‐like HA particles dispersing evenly in CS substrate. When [η]CS = 5.75 × 10?4, HA content = 65%, and crosslinking degree = 10%, the resulting CS/HA scaffolds had a flexural strength of 20 MPa and porosity of 60%, which could meet the requirements of bone repair materials. The scaffolds were used as drug carriers for icariin, and the impacts of loading time and crosslinking degree of scaffolds on drug‐loading dose were discussed. The suitable loading time was 24 h and it would be better to keep crosslinking degree no more than 10%. The drug release behavior demonstrated that the icariin‐loading CS/HA scaffolds could achieve basic drug sustained release effect. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1539–1547, 2013  相似文献   

8.
Random nanofibrous composite scaffolds of PVA/PCL bilayer were fabricated by electrospinning method. The bilayer nanofibrous scaffolds were subjected to detailed structural, morphological, chemical, and thermal analysis using XRD, SEM, FTIR, and DSC. Morphological investigations revealed that the prepared nanofibers have uniform morphology and the average fiber diameters for bilayer samples A, B, and C are 203, 252, and 244 nm, respectively. The obtained scaffolds have a porous structure with porosity of 77, 89.2, and 78.3 % for bilayer samples A, B, and C, respectively. FTIR analysis ensured complete evaporation of solvent and formation of non-interactive bilayers. Biocompatibility of the membranes was investigated by studying the adhesion of mouse NIH 3T3 fibroblasts for 72 h, and its enhanced adhesion and proliferation proved its mettle as a potential scaffold for tissue engineering applications.  相似文献   

9.
Cartilage tissue engineering is one of the interesting approaches used for repairing cartilage injuries. This study reports the fabrication of polyvinyl alcohol/alginate sulfate (PVA/ALG-S) nanofibrous mats as a functional support for chondrogenic differentiation of human bone marrow mesenchymal stem cells (hBM-MSCs). The PVA/ALG-S nanofibers were obtained through electrospinning of PVA solutions containing 10, 20, and 30 wt% of ALG-S. The appearance of a band at 833 cm−1 assigned to the symmetrical C O S vibration associated to a C O SO3 group confirmed the presence of ALG-S in nanofibrous mat. The SEM images illustrated the bead-free and smooth morphology of PVA/ALG-S nanofibers with a mean diameter of 185 ± 0.06 nm. The MTT assay of the hBM-MSCs seeded on scaffolds indicated the appropriate cytocompatibility of nanofibrous PVA/ALG-S scaffolds. Furthermore, the appropriate attachment and spreading of the hBM-MSCs based on SEM images, and their differentiation to the chondrocyte-like cells accompanied by a decrease in cell growth on MTT analysis and more color absorption in alician blue staining indicated the effective role of alginate sulfate on cell differentiation. Finally, the expression of Type II collagen by RT-PCR and immunocytochemistry analyses revealed the chondrogenic differentiation of hBM-MSCs on alginate sulfate nanofibers.  相似文献   

10.
We produced highly aligned porous poly(ε-caprolactone) (PCL)/hydroxyapatite (HA) scaffolds by unidirectionally freezing PCL/HA solutions with various HA contents (0, 5, 10 and 20 wt% in relation to the PCL polymer) and evaluated their mechanical properties and in vitro biocompatibility to examine their potential applications in bone tissue engineering. All the prepared scaffolds had a highly aligned porous structure, in which the HA particles were uniformly dispersed in the PCL walls. The elastic modulus of the PCL/HA scaffolds significantly increased from 0.12 ± 0.02 to 2.65 ± 0.05 MPa with increasing initial HA content from 0 to 20 wt%, whereas the pore size decreased from 9.2 ± 0.7 to 4.2 ± 0.8 μm. In addition, the PCL/HA scaffolds showed considerably enhanced in vitro cellular responses that were assessed in terms of cell attachment, proliferation and osteoblastic differentiation.  相似文献   

11.
Porous degradable scaffolds are used extensively in bone tissue engineering. As well as material type, the architectural and mechanical characterizations of scaffolds are important to facilitate cell and tissue growth. Matrices composed of hydroxyapatite (HA), chitosan (CS) and demineralized bone matrix (DBM) may create an appropriate environment for the regeneration of bones. In this study, CS/HA/DBM scaffolds with sufficient structural integrity and high interconnected porosity were produced using different combinations of CS, HA and DBM. Both mechanical and biological properties of porous scaffolds were determined by local microarchitecture whose parameters were quantified based on micro computed tomography (Micro-CT) analysis. Within porosity range of 48–65%, the ranges of average compressive modulus and ultimate strength of the scaffolds were 3 ± 1–6 ± 1 kPa and 11 ± 2–24 ± 2 kPa, respectively. With the increase of HA concentration at the equal weight of DBM, the average trabecular thickness and trabecular separation increased and bone surface/volume ratio decreased, resulting in higher volume fraction and lower total porosity. In vitro, MC3T3-E1 preosteoblast cells were used to investigate cell attachment, spreading and proliferation on the scaffolds via hematoxyline and eosin (HE), scanning electron microscopy (SEM) and MTS assay. The results showed that MC3T3-E1 cells adhered to the surface of composite scaffolds, cell number increased with culture time. Cell viability increased with the HA particles decreased, changed little with the DBM increased. Consideration of the microarchitectural and mechanical characterization and biocompatibility of the scaffolds, 3:3:1.5 and 3:5:1.5 groups were believed to be the best in our study.  相似文献   

12.
《Ceramics International》2021,47(19):26991-27001
Hydroxyapatite (HA) scaffolds were fabricated using the space holder method with a pressureless sintering process in a systematically developed manner at different fabrication stages to increase the strength of the scaffold at high porosity. Polyvinyl alcohol (PVA) and Polymethyl methacrylate (PMMA) were used as binders and space holder agents, respectively. The physical properties of the HA scaffolds were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), linear shrinkage test, and porosity measurements. The mechanical properties of the HA scaffolds were analyzed using compressive strength measurements. The results revealed that the HA scaffold met the expected quality requirements with a compressive strength of 2.2 MPa at a porosity of 65.6% with pore sizes distributed in the range of 126–385 μm. The shrinkage of the scaffold diameter occurred by 20.27%, this diameter shrinkage predominantly to the shrinkage of the HA scaffold caused by sintering. Besides, suspect that a higher PMMA concentration causes pore size shrinkage upon sintering. The formation of pore interconnections was evidenced by SEM observations and the ‘translucent light method’ developed in this study. The results of the scaffold phase test using XRD showed that the final scaffold consisted only of the HA phase, as the PVA and PMMA phases burned out during the sintering process.  相似文献   

13.
3D-printed scaffolds can better mimic the function of human skin, both biologically and mechanically. Within the scope of this study, the effect of the addition of different amounts (10, 15, 20 mg) of gentamicin sulfate (GS) to a 10 mL solution of natural and synthetic polymers is investigated. Sodium alginate (SA), gelatin-methacryloyl (GelMA), and polyvinyl alcohol (PVA) are chosen as bioactive materials. The surface morphology and pore structures are visualized by scanning electron microscopy (SEM). According to the results, it is observed that the pore sizes of all scaffolds are smaller than 270 µm, the lowest value (130 µm) is obtained in the scaffold loaded with 15 mg GS, and it also has the highest tensile strength value (12.5 ± 7.6 MPa). Similarly, it is observed that the tensile strength (9.7 ± 4.5 MPa) is high in scaffold loaded with 20 mg GS. The biocompatibility test is performed with fibroblast cells, and the results show that the scaffolds are biocompatible with cells. The antibacterial test is carried out against the S.aureous and E. coli and the results indicate that all GS-loaded scaffolds demonstrate antibacterial activity.  相似文献   

14.
The aim of this work was to develop bioactive chitosan scaffolds reinforced with monetite‐containing whisker‐like fibers. The fibers synthesized by homogeneous precipitation were characterized as monetite/hydroxyapatite short fibers (MAFs), using XRD, FTIR and SEM. The pure chitosan and MAFs/chitosan composite scaffolds were produced by freeze‐drying, and characterized with respect to porosity, pore size, swelling behavior, compressive strength and modulus, and in vitro bioactivity. The incorporation of MAFs in chitosan matrices led to increase the pore size, according to the evaluation by FE‐SEM, and decrease the porosity of composite scaffolds. The swelling ratio decreased as MAFs content of scaffolds increased. The compressive strength and modulus of scaffolds were improved by an increase in MAFs content. The noncross‐linked scaffolds with a chitosan: MAFs weight ratio of 1:1 (CW3) showed a porosity of 75.5%, and the strength and modulus of 259 kPa and 2.8 MPa in dry state, respectively. The crosslinking by glutaraldehyde resulted in improved mechanical properties. The strength and modulus of cross‐linked CW3 scaffolds in wet state reached to 345 kPa and 1.8 MPa, respectively. The in vitro bioactivity of the reinforced scaffolds, evaluated by FE‐SEM/EDS, XRD, and ATR‐FTIR, was confirmed by the formation of a carbonated apatite layer on their surfaces when they soaked in simulated body fluid (SBF). The results of this initial study indicate that the monetite‐containing whisker‐like fibers may be an appropriate reinforcement of chitosan scaffolds.  相似文献   

15.
Nanomaterials can be used as reinforcement phase to improve the performance of polymers. A simple method to prepare a composite film with super high tensile strength was used in this study. The properties of montmorillonite (MMT)/polyvinyl alcohol (PVA) films reinforced by chitin nanowhisker (CNW) have been evaluated. The structures and properties of films were analyzed by atomic force microscope (AFM), Fourier transforms infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and tensile testing. The results of FTIR and XRD showed that no chemical interaction occurred among MMT, PVA, and CNW. The SEM and AFM images suggested that the obtained composite films with the three substances had a relatively uniform layered structure and relatively smooth. The temperature at the onset of decomposition of the composite films was increased from 262.0 to 282.3°C by the addition of CNW. The tensile strength of the MMT/PVA/CNW film was reached 263.5 MPa, which was increased approximately 382% compared with the MMT/PVA film. According to these results, the composite film could be potentially used in packaging materials.  相似文献   

16.
Increasing mechanical strength of gelatin‐based materials is required to expand the range of their applications, which is desirable because of biocompatibility, biodegradability, and low cost of gelatin. The effect of aluminum potassium sulfate on preparation and properties of nanofibrous gelatin were investigated. Samples were electrospun from 10M aqueous acetic acid and analyzed by scanning electron microscopy (SEM), Fourier transform infrared microscopy (FTIR), energy‐dispersive x‐ray analysis (EDX), and tensile test. The addition of AlK(SO4)2 considerably increases the elastic modulus of the material up to about 10% salt content. The elastic modulus of electrospun gelatin meshes prepared as described in the present work increased from 20 MPa to 70 MPa and the elastic modulus of the fiber material increased from 150 MPa to 620 MPa as the salt content in the fibers increased from 0% to 9.6%. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42431.  相似文献   

17.
In this work, chitin flakes were deacetylated with 50% (w/v) sodium hydroxide under nitrogen atmosphere at 120 °C for 80 min to obtain chitosan. The chitosan produced was characterized for degree of deacetylation (DD) and molecular weight. Chitosan with the DD of 78–80% was reproducibly obtained. Molecular weight showed an inverse relationship with concentration of NaOH. Chitosan nanofibrous membrane was prepared via the electrospinning of chitosan/polyvinyl alcohol (CH/PVA) aqueous solutions with varying blend compositions. The characteristics of CH/PVA nanofibrous membranes were studied as a function of viscosity of solution and applied voltage. A uniform nanofibrous membrane of average fibre diameter of 80–300 nm was obtained with blend of 2% (w/v) chitosan solution in 1% (v/v) acetic acid and 5% (w/v) PVA in distilled water in the electric field of 20–25 kV with varying proportion of CH/PVA. With the CH/PVA mass ratios; 40/60 to 10/90, electrospinning of nanofibres could be done. The electrospun nanofibrous membrane was analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Thermo gravimetric analysis (TGA). SEM images showed that the morphology and diameter of the nanofibres were mainly affected by the weight ratio of CH/PVA. XRD and FTIR confirmed the strong intermolecular hydrogen bonding between the molecules of Chitosan and PVA.  相似文献   

18.
In this work, we aimed to develop a scaffold of chitosan (CS) with a porous sponge structure for an artificial skin. The scaffolds were prepared from both CS/citric and CS/acetic solutions. In addition, the cast films were also prepared from the same solutions to compare some of their properties. They were characterized using WAXD, FTIR, DSC, tensile measurements, and SEM observation. It was found that CS/acetate had low crystallinity but CS/citrate was in an amorphous state, resulting in a large ductility with rubbery softness. Despite the different morphologies of CS/citrate and CS/acetate scaffolds, both scaffolds exhibited the wound healing effect available for tissue engineering. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

19.
Poly(vinyl alcohol) (PVA)/montmorillonite clay (MMT) nanofiber mats have been fabricated by the electrospinning technique. The PVA/MMT nanofiber mats were characterized by X‐ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), Fourier transform infrared (FTIR), and mechanical measurements. The study showed that the introduction of MMT results in improvement in tensile strength, and thermal stability of the PVA matrix. XRD patterns and SEM micrographs suggest the coexistence of exfoliated MMT layers over the studied MMT contents. FTIR revealed that there might be possible interaction occurred between the MMT clay and PVA matrix. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

20.
This research investigated the injection-molding techniques to produce hydroxyapatite (HA)/ethylene-vinyl acetate (EVA)/polyamide 66 (PA66) composite scaffolds. The effects of HA, EVA, azodicarbonamide (AC) content and shot size on the mechanical properties, pore morphology, porosity and crystallization behavior of the composite scaffolds were analyzed by XRD, DSC, SEM and mechanical test. The compressive modulus and strength of the HA/EVA/PA66 scaffolds with a pore size of 200–600 µm are close to the cancellous bone. Compared with common methods to fabricate scaffolds, this process makes the fabrication of composite scaffolds come true in a rapid and convenient manner.  相似文献   

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