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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.
Bone shows a radial gradient architecture with the exterior densified cortical bone and the interior porous cancellous bone. However, previous studies presented uniform designs for bone scaffolds that do not mimic natural bone's gradient structure. Hence, mimicking native bone structures is still challenging in bone tissue engineering. In this study, a novel biomimetic bone scaffold with Haversian channels is designed, which approximates mimicking the native bone structure. Also, the influence of adding graphene oxide (GO) to polycaprolactone (PCL)-based scaffolds are investigated by preparing PCL/GO composite ink containing 0.25% and 0.75% GO and then 3D printing scaffolds by an extrusion-based machine. Scanning electron microscopy (SEM) is used for morphological analysis. SEM reveals good printability and interconnected pore structure. The contact angle test shows that wettability reinforces with the increase of GO content. The mechanical behavior of the scaffolds under compression is examined numerically and experimentally. The results indicate that incorporation of GO can affect bone scaffolds' Young's modulus and von Mises stress distribution. Moreover, the biodegradation rates accelerate in the PCL/GO scaffolds. Biological characterizations, such as cell growth, viability, and attachment, are performed utilizing osteoblast cells. Compared to pure PCL, an enhancement is observed in cell viability in the PCL/GO scaffolds.  相似文献   

3.
In this study, biomedical thermoplastic polyurethane/graphene oxide (TPU/GO) composite scaffolds were successfully prepared using the thermally induced phase separation (TIPS) technique. The microstructure, morphology, and thermal and mechanical properties of the scaffolds were characterized by Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), and compression tests. Furthermore, NIH 3T3 fibroblast cell viability on the porous scaffolds was investigated via live/dead fluorescent staining and SEM observation. FTIR and Raman results verified the presence of GO in the composites. SEM images showed that the average pore diameter of the composite scaffolds decreased as the amount of GO increased. Additionally, the surface of the specimens became rougher due to the embedded GO. The compressive modulus of composite specimens was increased by nearly 200% and 300% with the addition of 5% and 10% GO, respectively, as compared with pristine TPU. 3T3 fibroblast culture results showed that GO had no apparent cytotoxicity. However, high loading levels of GO may delay cell proliferation on the specimens. POLYM. COMPOS., 35:1408–1417, 2014. © 2013 Society of Plastics Engineers  相似文献   

4.
《Ceramics International》2022,48(15):21378-21388
This report aimed to evaluate the mechanical behavior, bioactivity, and cytotoxicity of novel chitosan/akermanite-TiO2 (CS/AK/Ti) composite scaffolds fabricated using the 3D-printing method. The morphological and structural properties of these scaffolds were characterized by Fourier transform spectroscopy (FTIR) and scanning electron microscopy (SEM). The mechanical behavior was examined by measuring the compressive strength, while the bioactivity was estimated in the simulated body fluid (SBF), and also the cytotoxicity of the scaffolds was assessed by conducting cell culturing experiments in vitro. It was found that the mechanical properties were considerably affected by the amount of TiO2. The scaffolds had the possessed bone-like apatite forming ability, which indicated high bioactivity. Furthermore, L929 cells spread well on the surface, proliferated, and had good viability regarding the cell behaviors. The outcomes confirmed that the morphological, biological, and mechanical properties of developed 3D-composite scaffolds nearly mimicked the features of natural bone tissue. In summary, these findings showed that the 3D-printed scaffolds with an interconnected pore structure and improved mechanical properties were a potential candidate for bone tissue applications.  相似文献   

5.
The mechanical properties of biomedical scaffolds are important for applications in tissue regeneration. The dispensing system described herein, which is based on a solid free‐form fabrication technique, enables the production of design‐based scaffolds with controllable pore structures. Although current plotting systems can easily fabricate a variety of three‐dimensional scaffolds, the mechanical properties of these constructs are difficult to control because of low processing speed. To overcome this limitation, a new dispensing method, which uses a piezoelectric vibration system to improve mechanical properties, has been developed. Polycaprolactone (PCL) strands fabricated using this technique were roughly 70% stronger than normal PCL strands. To explain this increase in mechanical strength, the combined effects of the piezoelectric system and the melt‐dispensing process on the crystalline morphology and molecular orientation of PCL strands were investigated. POLYM. ENG. SCI., 2011. © 2010 Society of Plastics Engineers  相似文献   

6.
Considerable efforts have been devoted toward the development of electrospun scaffolds based on poly(ε‐caprolactone) (PCL) for bone tissue engineering. However, most of previous scaffolds have lacked the structural and mechanical strength to engineer bone tissue constructs with suitable biological functions. Here, we developed bioactive and relatively robust hybrid scaffolds composed of diopside nanopowder embedded PCL electrospun nanofibers. Incorporation of various concentrations of diopside nanopowder from 0 to 3 wt % within the PCL scaffolds notably improved tensile strength (eight‐fold) and elastic modulus (two‐fold). Moreover, the addition of diopside nanopowder significantly improved bioactivity and degradation rate compared to pure PCL scaffold which might be due to their superior hydrophilicity. We investigated the proliferation and spreading of SAOS‐II cells on electrospun scaffolds. Notably, electrospun PCL‐diopside scaffolds induced significantly enhanced cell proliferation and spreading. Overall, we concluded that PCL‐diopside scaffold could potentially be used to develop clinically relevant constructs for bone tissue engineering. However, the extended in vivo studies are essential to evaluate the role of PCL‐diopside fibrous scaffolds on the new bone growth and regeneration. Therefore, in vivo studies will be the subject of our future work. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44433.  相似文献   

7.
Bone tissue scaffolds should have both desired mechanical stability and cell activities including biocompatibility, cell differentiation, and maturation. Also, suitable mineralization is another key factor for these materials. Hence, in current work, in order to achieve a scaffold with desired mechanical and bioactivity properties, core-shell nanofibers based on the polycaprolactone and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) with different concentration of graphene oxide (GO) (0.5, 1, and 1.5 wt%) and calcium phosphate (CP) (1 and 3 wt%) were prepared to utilize as bone scaffold. Microstructure of nanofibers observed by field emission scanning electron microscope (FE-SEM) and results exhibited that the most of nanofibers had 270–500 nm diameter. Attenuated total reflectance Fourier transform infrared spectroscopy and energy dispersive X-ray evaluations verified appearance of GO and CP into the electrospun scaffolds (ES). Transmission electron microscopy analysis endorsed core-shell structure of nanofibers. X-ray diffraction study moreover determination of semicrystalline structure, verified presence of GO and CaPO4 into the nanofibers. Water contact angle demonstrates that, ES2 and ES3 situated in suitable domain of hydrophilicity. Tensile analysis determined that, ES2, ES3, and ES4 had the highest mechanical properties for use as bone scaffold. Cell viability assessment confirmed biocompatibility of scaffold during 7 days. Alkaline phosphatase and alizarin red staining exhibited maturating and differentiating of osteocytes after 21 days seeding on the scaffolds.  相似文献   

8.
In this study, bismuth doped 45S5 nanobioactive bioglass (nBG) and graphene oxide (GO) nanocomposites were developed and characterized in terms of microstructural, mechanical, bioactivity and biological properties. Bismuth (Bi) - doped nBG was synthesized by sol-gel method and sintered at 600 °C for 2 h. Nanosized GO was homogeneously mixed with Bi doped bioglass at various ratios to prepare nanocomposites. Addition of Bi increased the density of nBG samples while a considerable decrease in density was observed for nanocomposites with GO incorporation. Bi improved the diametral tensile strength of nBG and addition of 2.5% GO to the composite also increased the diametral tensile strength of the nanocomposites. However, addition of more than 2.5% GO had negative effect on the diametral tensile strength of the composites. Bi doping to bioglass and its composite with GO increased the biocompatibility of 45S5 nBG in which 96.5BG1Bi2.5GO (containing 96.5% BG 1% Bi 2.5% GO in weight ratio) showed highest cell viability. Overall, it can be concluded that composites of Bi doped 45S5 nBG with GO hold promise as biomaterial for biomedical applications.  相似文献   

9.
Dextrin and dextrin‐polyethylene oxide (DEX/PEO) fibers in the submicron range were produced by electrospinning of single and blend polymer solutions. The morphology, intermolecular interactions, and mechanical properties of dextrin microfibers with and without PEO were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, X‐ray diffraction, nuclear magnetic resonance spectroscopy, and uniaxial tensile testing. Spectroscopic results confirmed hydrogen bond formation, evidencing dextrin as a molecular entanglement source for fiber mechanical reinforcement. The uniaxial tensile tests demonstrated a synergistic mechanical reinforcement effect that varied with blend composition. Equal weight ratio blends supported a maximum tensile strength with a high elastic modulus and demonstrated to be more elastic and resistant to breaking, even than pristine PEO fibers. Moreover, elastic moduli of blend fiber mats were found to lie within the value range for human skin, thus providing the DEX/PEO meshes with potential applicability as skin tissue scaffolds. This synthesis approach proved the feasible and inexpensive fabrication process of natural‐synthetic polymer hybrid fibers that combine the biocompatibility, biodegradability, and encapsulating capability of dextrin with the mechanical strength and flexibility of PEO for the development of scaffolds for tissue engineering and topical drug delivery applications in skin wound healing. POLYM. ENG. SCI., 59:1778–1786, 2019. © 2019 Society of Plastics Engineers  相似文献   

10.
Composite materials based on a combination of biodegradable polymers and bioactive ceramics, including chitosan and hydroxyapatite are discussed as suitable materials for scaffold fabrication. Diopside is a member of bioactive silicates; it is a good choice for hard tissue engineering because of its biocompatibility with host tissue and high mechanical strength. Chitosan and hydroxyapatite were extracted from shrimp shell and bovine bone, respectively and diopside nanoparticles were prepared by the sol-gel method. The present study reports on a chitosan composite which was reinforced by hydroxyapatite and diopside; the scaffolds were fabricated by the freeze-drying method. The so-produced chitosan-hydroxyapatite-diopside (CS-HA-DP) scaffolds were further cross-linked using tripolyphosphate (TPP) to achieve enhanced mechanical strength. The ratios of the ceramic components in composites were 5-58-37, 10-55-35, and 15-52-33 (diopside-hydroxyapatite-chitosan, w/w %). The physicochemical properties of scaffolds were investigated using Fourier-transform infrared spectrometry (FT-IR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS) techniques. The effect of scaffolds composition on bioactivity and biodegradability were studied well. To investigate mechanical properties of samples, compression test was done. Results showed that the composite scaffold with 5% DP has the highest mechanical strength. The porosity of composites dropped from 92% to 76% by increasing the amount of DP. Cytocompatibility of the scaffolds was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, alkaline phosphatase (ALP) activity, and cell attachment studies using human osteoblast cells. Results demonstrated no sign of toxicity and cells were found to be attached to the pore walls within the scaffolds; moreover, results illustrated that the developed composite scaffolds could be a potential candidate for tissue engineering.  相似文献   

11.
For soft tissue engineering applications, 3-D macroporous acetylated chitosan/poly(l-lactideco-ε-caprolactone) (PLCL) scaffolds were prepared by acetylation and particulate leaching using sodium acetate in an acidic water/dioxane solution. Acetylated 5 wt% chitosan/PLCL scaffold of 90% porosity was determined and confirmed through various tests. The physiochemical properties of acetylated chitosan/PLCL hybrid scaffolds were examined by measuring water contact angles, pore morphology and interconnectivity using scanning electron microscopy (SEM), and dye release testing. In addition, mechanical properties such as tensile strength and bending stress recovery for determining the elasticity of scaffolds were measured. The fibroblast cell line NIH-3T3 was used to test relative cell affinities for the acetylated chitosan/PLCL vs. normal chitosan/PLCL films and porous scaffolds. The acetylated chitosan/PLCL films and scaffolds showed a high initial cell adhesion after 4 h of cell culture and increased cell proliferation compared to that of the control. The acetylated chitosan/PLCL scaffolds produced by particulate leaching showed a highly porous structure and improved the biocompatibility and stability of chitosan compared to that of chitosan-coated PLCL scaffolds. Thus, these scaffolds may be very useful for a variety of tissue engineering applications.  相似文献   

12.

Medicinal plants such as Calendula officinalis (C. officinalis) are commonly used for skin wounds’ treatment. On the other hand, gum arabic (GA) has a lot of potential for use in wound healing because of its unique physio-chemical properties. Wound healing activity of gum arabic (GA) and Calendula officinalis (C. officinalis) along with good mechanical properties of poly (ε-caprolactone) (PCL) can produce a suitable nanofibrous scaffold for skin tissue engineering as well as wound dressing application. In this study, PCL/C. officinalis/GA nanofibrous scaffolds with diameter distribution in the range of 85–290 nm were prepared via electrospinning. Characteristics of the nanofibrous scaffolds, i.e., morphology, scaffold compounds, porosity, mechanical and antibacterial properties, hydrophilicity and degradability in phosphate buffer saline (PBS) were investigated. Cell viability and proliferation of scaffolds were evaluated by MTT [3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide] assay. Results indicated that hydrophilicity of the PCL/C. officinalis/GA scaffolds was higher than the PCL scaffold. The tensile strength and elongation of the PCL/C. officinalis/GA scaffolds were in the range of 2.13–4.41 MPa and 26.37–74.37%, respectively, which are very suitable for skin tissue engineering. The porosity of the scaffolds was higher than 60% and was appropriate for the proliferation of fibroblast cells. The nanocomposite scaffold also showed suitable degradability and antimicrobial activity. Moreover, cell culture indicated that GA and C. officinalis promoted cell attachment and proliferation. It can be concluded that the nanofibrous calendula-loaded PCL/GA scaffolds are well suited for regenerating skin.

  相似文献   

13.
The multi-sized porous β-tricalcium phosphate scaffolds were fabricated by freeze drying followed by slurry coating using a multi-sized porous sponge as a template. Then, gelatin was dip coated on the multi-sized porous β-tricalcium phosphate scaffolds under vacuum. The mechanical and biological properties of the fabricated scaffolds were evaluated and compared to the uniformly sized porous scaffolds and scaffolds that were not coated by gelatin. The compressive strength was tested by a universal testing machine, and the cell viability and differentiation behavior were measured using a cell counting kit and alkaline phosphatase activity using the MC3T3-E1 cells. In comparison, the gelatin-coated multi-sized porous β-tricalcium phosphate scaffold showed enhanced compressive strength. After 14 days, the multi-sized pores were shown to affect cell differentiation, and gelatin coatings were shown to affect the cell viability and differentiation. The results of this study demonstrated that the multi-sized porous β-tricalcium phosphate scaffold coated by gelatin enhanced the mechanical and biological strengths.  相似文献   

14.
Hybrid nanomaterials fabricated by the heterogeneous integration of 1D (carbon nanotubes) and 2D (graphene oxide) nanomaterials showed synergy in electrical and mechanical properties. Here, we reported the infiltration of carboxylic functionalized single-walled carbon nanotubes (C-SWNT) into free-standing graphene oxide (GO) paper for better electrical and mechanical properties than native GO. The stacking arrangement of GO sheets and its alteration in the presence of C-SWNT were comprehensively explored through scanning electron microscopy, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction. The C-SWNTs bridges between different GO sheets produce a pathway for the flow of electrical charges and provide a tougher hybrid system. The nanoscopic surface potential map reveals a higher work function of the individual functionalised SWNTs than surrounded GO sheets showing efficient charge exchange. We observed the enhanced conductivity up to 50 times and capacitance up to 3.5 times of the hybrid structure than the GO-paper. The laminate of polystyrene composites provided higher elastic modulus and mechanical strength when hybrid paper is used, thus paving the way for the exploitation of hybrid filler formulation in designing polymer composites.  相似文献   

15.
Poly-lactic acid (PLA) is a biodegradable polymer that has been well accepted as a tissue engineering scaffold material. Recently, PLA has been applied in selective vacuum manufacturing (SVM), a new RP technique being developed, for fabricating scaffold. For this RP technique to be accepted for this purpose, its fabricated scaffolds must be tested for their properties. This paper presents an investigation of the properties of scaffolds fabricated from SVM technique. The results illustrated that the fabricated PLA scaffolds had porous structure. The porosity was about 71.65% with pore size ranged from 20 to 90???m. The compressive modulus of elasticity was 2.07?±?0.25?MPa, lying within the lower range of mechanical properties reported for soft tissue application. An indirect cytotoxicity test showed the cell viability of 75.92% which means that the specimens posed no threat to the cells and could be used as scaffolds for mammalian tissue culture.  相似文献   

16.
Tissue engineering has been widely used in regenerative medicine and tissue engineering scaffolds have become a new research direction for periodontal regenerative repair. We aim to develop a biological scaffold material that can support host immunity and promote periodontal regeneration. In this paper, chitosan (CS)/polyvinyl alcohol (PVA)/graphene oxide (GO)/astaxanthin (ASTA) nanofibers membranes were prepared by electrospinning. The nanofibers were characterized by scanning electron microscopy, infrared spectroscopy, mechanical testing, antibacterial testing and cytotoxicity testing. The CS/PVA/GO/ASTA nanofiber membrane had favorable micro-morphology, good mechanical properties and no cytotoxicity. This preliminary study demonstrates that the CS/PVA/GO/ASTA nanofiber membrane can be used for in vivo and in vitro experiments related to periodontal regeneration. The related mechanism of periodontal regeneration will be evaluated in future studies.  相似文献   

17.
We aim to investigate the potential of collagen extracted from rainbow trout for tissue engineering applications. In this regard, nanocomposite scaffolds based on the extracted collagen reinforced with various concentrations of boron nitride (BN) nanoparticles (0, 3, 6, 9, and 12 wt%) were developed. In addition, the role of various concentrations of BN nanoparticles and two-step cross-linking process on the physical and chemical properties of nanocomposite scaffolds were investigated. Our results demonstrated the isolation of Type I collagen with excellent thermal stability but with some structural and chemical differences compared to other sources. The synergic role of BN nanoparticles and two-step cross-linking process resulted in a noticeable improvement in the mechanical properties of collagen-BN scaffolds. Noticeably, incorporation of 6 wt% BN along with a two-step cross-linking process significantly increased the compressive strength (9.5 times) and elastic modulus (four times) of the collagen scaffold. Besides, nanocomposite scaffolds significantly improved proliferation and spreading of MG-63 cell line, confirming their biocompatibility. The results suggested that the incorporation of BN nanoparticles along with a two-step cross-linking process not only could promote the mechanical and thermal performances of collagen scaffolds, but also enhanced high cell viability, and proliferation supporting their potential in tissue engineering applications.  相似文献   

18.
Graphene oxide (GO) based hydrogels were proposed to be used as biomaterials and stimuli-response materials, but their poor mechanical properties restricted their applications. We enhanced GO–poly(N-isopropylacrylamide) (PNIPAm) hydrogels by hybrid with the hectorite clay through in situ polymerization for the first time. This clay was found to stabilize the GO in the aqueous suspension when a reducer was added in a redox initiating pair. These GO–clay–PNIPAm hybrid hydrogels exhibited a high mechanical strength and extensibility with the GO sheets as the cross-linker and with the hectorite clay as both the cross-linker and reinforcing agent. They were thermal-responsive with the volume phase transition at ∼34 °C. Reduction of the GO with l-ascorbic acid under environmental friendly conditions resulted in a high conductivity to the graphene–clay–PNIPAm hydrogels. These graphene–clay–PNIPAm hydrogels still had desirable mechanical properties. This finding has provided an easy method to prepare strong and stimuli-response graphene–polymer hydrogels to meet the demand for the newly developed soft matter.  相似文献   

19.
选择丙烯酸酯作为自由基型预聚物,3,4–环氧环己基甲基–3,4环氧环己基甲酸酯作为阳离子型预聚物,三丙二醇二丙烯酸酯为活性稀释剂,2,2–二甲基–α–羟基苯乙酮和三芳基硫鎓盐为光引发剂来制备一种混杂固化光敏树脂。将聚氨酯丙烯酸酯(PUA)加入到上述制备的光敏树脂中,探究PUA作为辅助预聚物对光敏树脂性能的影响,用超声分散法制备了纳米氧化石墨烯(GO)改性光敏树脂复合材料。当PUA的质量分数为20%时,力学性能最优;GO对光敏树脂的力学性能有改善的作用,拉伸强度从17.84 MPa最大增强至27.84 MPa,提高了56%;且该混合体系的体积收缩率在3%左右,线收缩率也很小。  相似文献   

20.
To engineer tissue restoration, it is necessary to provide a bioactive, mechanically robust scaffold. Electrospun poly(ε‐caprolactone) (PCL) nanofiber is a promising biomaterial candidate with excellent mechanical properties, but PCL scaffolds are inert and lack natural cell recognition sites. To overcome this problem we investigated the incorporation of Antheraea pernyi silk fibroin (ASF) containing inherent RGD tripeptides with PCL in electrospinning process. The mixing ratios showed remarkable impact on the properties of hybrid nanofibers. Increasing PCL content significantly enhanced the mechanical properties of nanofibers. In particular, the mechanical properties were remarkably enhanced when PCL content increased from 50 wt% to 70 wt%. Moreover, the biological assays based on endothelial cells showed promoted cell viability when ASF content reached to 30 wt%. The data demonstrated that the nanofiber containing 70% of PCL and 30% of ASF achieved the most balanced performances for integrating the mechanical properties of PCL and the bioactivity of ASF. Furthermore, biomimetic alignment of 70PCL/30ASF nanofibers was achieved, which could support PC12 neuron‐like cell growth and guide neurite outgrowth, providing a potentially useful option for the engineering of oriented tissues. The results show that the PCL/ASF hybrid nanofibers can be considered as a promising candidate for tissue engineering scaffolds. POLYM. ENG. SCI., 57:206–213, 2017. © 2016 Society of Plastics Engineers  相似文献   

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