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1.
Xin Liu Zongping Xie Changqing Zhang Haobo Pan Mohamed N. Rahaman Xin Zhang Qiang Fu Wenhai Huang 《Journal of materials science. Materials in medicine》2010,21(2):575-582
The objective of this work was to evaluate borate bioactive glass scaffolds (with a composition in the system Na2O–K2O–MgO–CaO–B2O3–P2O5) as devices for the release of the drug Vancomycin in the treatment of bone infection. A solution of ammonium phosphate,
with or without dissolved Vancomycin, was used to bond borate glass particles into the shape of pellets. The in vitro degradation
of the pellets and their conversion to a hydroxyapatite-type material in a simulated body fluid (SBF) were investigated using
weight loss measurements, chemical analysis, X-ray diffraction, and scanning electron microscopy. The results showed that
greater than 90% of the glass in the scaffolds degraded within 1 week, to form poorly crystallized hydroxyapatite (HA). Pellets
loaded with Vancomycin provided controlled release of the drug over 4 days. Vancomycin-loaded scaffolds were implanted into
the right tibiae of rabbits infected with osteomyelitis. The efficacy of the treatment was assessed using microbiological
examination and histology. The HA formed in the scaffolds in vivo, resulting from the conversion of the glass, served as structure
to support the growth of new bone and blood vessels. The results in this work indicate that bioactive borate glass could provide
a promising biodegradable and bioactive material for use as both a drug delivery system and a scaffold for bone repair. 相似文献
2.
Xin-Hui Xie Xiao-Wei Yu Shao-Xian Zeng Rui-Lin Du Yu-Huai Hu Zhen Yuan Er-Yi Lu Ke-Rong Dai Ting-Ting Tang 《Journal of materials science. Materials in medicine》2010,21(7):2165-2173
We conducted histologic and histomorphometric studies to evaluate the osteointegration of gradient coatings composed of bioactive
glass and nanohydroxyapatite (BG–nHA) on titanium-alloy orthopaedic implants and surrounding bone tissue in vivo. Titanium-alloy
implants with a gradient coating (gradient coating group), uncoated implants (uncoated group), and implants with a conventional
hydroxyapatite (HA) coating (HA coating group) were randomly implanted in bilateral femoral condyles of 36 male New Zealand
rabbits. The bone–implant contact at 12 and 24 weeks and the new bone volume in the notch created for observing bone ingrowth
at 4, 12, and 24 weeks were found greater in the gradient coating group than those in both the uncoated group and the HA coating
group (p < 0.05). Fluorescence micrographs showed active osteogenesis in the gradient coating group at 4 weeks after implantation.
These findings indicated that BG–nHA gradient coatings could enhance the osteointegration of orthopaedic implant. 相似文献
3.
Effects of Ti2448 half-pin with low elastic modulus on pin loosening in unilateral external fixation
Zheng K Li X Fu J Fan X Wang P Hao Y Li S Fan H Guo Z 《Journal of materials science. Materials in medicine》2011,22(6):1579-1588
The objective of this study was to compare the benefits of titanium 2448 (Ti2448) half-pin and titanium-6 aluminium-4 vanadium
(TAV) half-pin on reducing pin loosening during external fracture fixation. Although having similar strength, Ti2448 half-pin
had even lower elastic modules(33 GPa)when compared with TAV half-pin (110 GPa), which was similar to that of cortical bone
(20 GPa). In the external fixation of tibial model fractures and canine cadaveric tibia fractures, Ti2448 half-pin had greater
recoverable deformation and less stress concentration at the pin–bone interface in compression, torsion, and four-points bending
test. Then, tibial fractures were created in 24 dogs and stabilized with four half-pins of either Ti2448 or TAV in each animal.
At 4 and 8 weeks postoperatively, fracture healing and pin loosening was assessed by radiographic grading scale. The scores
of Ti2448 group were significantly higher than those of TAV group. Micro-CT analysis also indicated larger quantity and higher
quality of newly formed bone at pin–bone interface in Ti2448 group. Histology observation showed the newly formed bone integrated
well into the threads of Ti2448 half-pins. In contrast, there was a layer of necrotic tissue between the bone tissue and TAV
half-pin at pin–bone interface in TAV group. The extraction torque values of Ti2448 half-pins near the fracture line were
significantly higher than those TAV pins. In conclusion, the Ti2448 half-pin with low elastic modulus could enhance osseointegration
and reduce pin loosening when compared with TAV half-pin. It is a promising biomaterial for constructing external fixation
system in clinical application. 相似文献
4.
Doiphode ND Huang T Leu MC Rahaman MN Day DE 《Journal of materials science. Materials in medicine》2011,22(3):515-523
A solid freeform fabrication technique, freeze extrusion fabrication (FEF), was investigated for the creation of three-dimensional
bioactive glass (13–93) scaffolds with pre-designed porosity and pore architecture. An aqueous mixture of bioactive glass
particles and polymeric additives with a paste-like consistency was extruded through a narrow nozzle, and deposited layer-by-layer
in a cold environment according to a computer-aided design (CAD) file. Following sublimation of the ice in a freeze dryer,
the construct was heated according to a controlled schedule to burn out the polymeric additives (below ~500°C), and to densify
the glass phase at higher temperature (1 h at 700°C). The sintered scaffolds had a grid-like microstructure of interconnected
pores, with a porosity of ~50%, pore width of ~300 μm, and dense glass filaments (struts) with a diameter or width of ~300 μm.
The scaffolds showed an elastic response during mechanical testing in compression, with an average compressive strength of
140 MPa and an elastic modulus of 5–6 GPa, comparable to the values for human cortical bone. These bioactive glass scaffolds
created by the FEF method could have potential application in the repair of load-bearing bones. 相似文献
5.
S. Murphy D. Boyd S. Moane M. Bennett 《Journal of materials science. Materials in medicine》2009,20(11):2207-2214
Controlled delivery of active ions from biomaterials has become critical in bone regeneration. Some silica-based materials,
in particular bioactive glasses, have received much attention due to the ability of their dissolution products to promote
cell proliferation, cell differentiation and activate gene expression. However, many of these materials offer little therapeutic
potential for diseased tissue. Incorporating trace elements, such as zinc and strontium, known to have beneficial and therapeutic
effects on bone may provide a more viable bone graft option for those suffering from metabolic bone diseases such as osteoporosis.
Rational compositional design may also allow for controlled release of these active ions at desirable dose levels in order
to enhance therapeutic efficacy. In this study, six differing compositions of calcium–strontium–sodium–zinc–silicate (Ca–Sr–Na–Zn–Si)
glass bone grafts were immersed in pH 7.4 and pH 3 solutions to study the effect of glass composition on zinc and strontium
release in a normal and extreme physiological environment. The zinc release levels over 30 days for all zinc-containing glasses
in the pH 7.4 solution were 3.0–7.65 ppm. In the more acidic pH 3 environment, the zinc levels were higher (89–750 ppm) than
those reported to be beneficial and may produce cytotoxic or negative effects on bone tissue. Strontium levels released from
all examined glasses in both pH environments similarly fell within apparent beneficial ranges—7.5–3500 ppm. Glass compositions
with identical SrO content but lower ZnO:Na2O ratios, showed higher levels of Sr2+ release. Whereas, zinc release from zinc-containing glasses appeared related to ZnO compositional content. Sustainable strontium
and zinc release was seen in the pH 7.4 environment up to day 7. These results indicate that the examined Ca–Sr–Na–Zn–Si glass
compositions show good potential as therapeutic bone grafts, and that the graft composition can be tailored to allow therapeutic
levels of ions to be released. 相似文献
6.
Yifei Gu Wei Xiao Linnan Lu Wenhai Huang Mohamed N. Rahaman Deping Wang 《Journal of Materials Science》2011,46(1):47-54
Borate bioactive glasses are receiving increasing attention as scaffold materials for bone repair and regeneration. In this
study, the kinetics and mechanisms of converting three groups of sodium–calcium–borate glasses with varying CaO:B2O3 ratio to hydroxyapatite (HA) in 0.25 M K2HPO4 solution were investigated at 10–70 °C. Glass disks with the composition 2Na2O·(2 − x)CaO·(6 + x)B2O3 (x = 0, 0.5, and 1.0) were immersed for up to 8 days in the potassium phosphate solution. The conversion kinetics to HA were
monitored by measuring the weight loss of the glass, while X-ray diffraction, scanning electron microscopy, and Fourier transform
infrared spectroscopy were used to study structural and compositional changes. All three groups of glasses formed HA on their
surfaces, showing that the glasses were bioactive. At 10–37 °C, the conversion kinetics was well fitted by the contracting
sphere model. Also, the contracting sphere model has a good fit for the early stage of conversion at 70 °C, whereas a three-dimensional
(3D) diffusion model provided a good fit to the data of the later stage. The results of this study provide kinetic and structural
data for the design of borate bioactive glasses for potential applications in bone tissue engineering. 相似文献
7.
Zhu XS Zhang ZM Mao HQ Geng DC Zou J Wang GL Zhang ZG Wang JH Chen L Yang HL 《Journal of materials science. Materials in medicine》2011,22(1):159-164
New injectable bone substitutes have been developed that are, unlike polymethylmethacrylate, biologically active and have
an osteogenic effect leading to osteogenesis and bone remodeling for vertebroplasty or kyphoplasty. In this study, we developed
a sheep vertebral bone defect model to evaluate the new bioactive materials and assessed the feasibility of the model in vivo.
Bone voids were experimentally created on lumbar vertebrae L2–L5 with L1 and L6 left intact as a normal control in mature
sheep. The defect vertebrae L2–L5 in each sheep were randomized to receive augmentation with calcium phosphate cement (CPC)
or sham. Vertebrae (L1–L6) were collected after 2 and 24 weeks of the cement augmentation and their strength and stiffness,
as well as osseointegration activity and biodegradability, were evaluated. Finally, CPC significantly improved the strength
and stiffness of vertebrae but did not yet restore it to the normal level at 24 weeks. Osteogenesis occurred at a substantially
high level after 24 weeks of CPC augmentation or sham. Therefore, the sheep vertebral model with one void, 6.0 mm in diameter
and 15.0 mm in depth, is replicable and can be used for evaluating the new injectable bioactive materials in vertebral augmentation
or reconstruction. 相似文献
8.
J. Suwanprateeb R. Sanngam W. Suvannapruk T. Panyathanmaporn 《Journal of materials science. Materials in medicine》2009,20(6):1281-1289
In situ hydroxyapatite/apatite–wollastonite glass ceramic composite was fabricated by a three dimensional printing (3DP) technique
and characterized. It was found that the as-fabricated mean green strength of the composite was 1.27 MPa which was sufficient
for general handling. After varying sintering temperatures (1050–1300°C) and times (1–10 h), it was found that sintering at
1300°C for 3 h gave the greatest flexural modulus and strength, 34.10 GPa and 76.82 MPa respectively. This was associated
with a decrease in porosity and increase in densification ability of the composite resulting from liquid phase sintering.
Bioactivity tested by soaking in simulated body fluid (SBF) and In Vitro toxicity studies showed that 3DP hydroxyapatite/A–W
glass ceramic composite was non-toxic and bioactive. A new calcium phosphate layer was observed on the surface of the composite
after soaking in SBF for only 1 day while osteoblast cells were able to attach and attain normal morphology on the surface
of the composite. 相似文献
9.
Bo Wang Yongping Pu Haidong Wu Kai Chen Ning Xu 《Journal of Materials Science: Materials in Electronics》2012,23(2):612-617
The effect of SrO–B2O3–SiO2 glass additive (SBS) on the microstructure and dielectric properties of CaCu3Ti4O12 (CCTO) ceramics was investigated. This SBS–added CCTO ceramics were prepared by the solid state reaction. The undesirable
impurity phases Ca3SiO5 started appearing in the XRD patterns, suggesting a possible chemical reaction between CaTiO3 and SiO2 (the devitrification production of SBS glass). The SBS glass additive promoted the grain growth and densification of CCTO
ceramics. Cole–Cole plots of conductance suggested that the resistivity grain boundary decreased with increasing amount of
SBS glass (when x = 0–2 wt%), then increased (when x = 2–3 wt%). The addition of SBS glass was desirable to increase the dielectric constants (up to 104) and lowered the dielectric losses of CCTO over the frequency range of 450–40 kHz at the relatively lower sintering temperature
for relatively shorter sintering time (1,050 °C, 12 h). 相似文献
10.
Sheng Yue Peter D. Lee Gowsihan Poologasundarampillai Zhengzhong Yao Peter Rockett Andrea H. Devlin Christopher A. Mitchell Moritz A. Konerding Julian R. Jones 《Journal of materials science. Materials in medicine》2010,21(3):847-853
X-ray microtomography (μCT) is a popular tool for imaging scaffolds designed for tissue engineering applications. The ability
of synchrotron μCT to monitor tissue response and changes in a bioactive glass scaffold ex vivo were assessed. It was possible
to observe the morphology of the bone; soft tissue ingrowth and the calcium distribution within the scaffold. A second aim
was to use two newly developed compression rigs, one designed for use inside a laboratory based μCT machine for continual
monitoring of the pore structure and crack formation and another designed for use in the synchrotron facility. Both rigs allowed
imaging of the failure mechanism while obtaining stress–strain data. Failure mechanisms of the bioactive glass scaffolds were
found not to follow classical predictions for the failure of brittle foams. Compression strengths were found to be 4.5–6 MPa
while maintaining an interconnected pore network suitable for tissue engineering applications. 相似文献
11.
Jeong-Cheol Lee Sung Baek Cho Seung Jin Lee Sang-Hoon Rhee 《Journal of Materials Science》2009,44(17):4531-4538
Nucleation and growth mechanism of apatite on a bioactive and degradable PLLA/SiO2–CaO composite with a thick PLLA surface layer were investigated compared to that on a bioactive but non-degradable polyurethane
(PU)/SiO2–CaO composite with a thick PU surface layer. The bioactive SiO2–CaO particles were made by a sol–gel method from tetraethyl orthosilicate and calcium nitrate tetrahydrate under acidic condition
followed by heat treatment at 600 °C for 2 h. The PLLA/SiO2–CaO and PU/SiO2–CaO composites were then prepared by a solvent casting method which resulted in thick PLLA and PU surface layers, respectively,
due to precipitation of SiO2–CaO particles during the casting process. Two composites were exposed to SBF for 1 week and this exposure led to form uniform
and complete apatite coating layer on the PLLA/SiO2–CaO composite but not on the PU/SiO2-CaO composite. These results were interpreted in terms of the degradability of the polymers. A practical implication of the
results is that a post-surface grinding or cutting processes to expose bioactive ceramics to the surface of a composite with
a thick biodegradable polymer layer is not required for providing apatite forming ability, which has been considered as one
of the pragmatic obstacles for the application as a bone grafting material. 相似文献
12.
Atiar Rahaman Molla Bikramjit Basu 《Journal of materials science. Materials in medicine》2009,20(4):869-882
The design and development of glass ceramic materials provide us the unique opportunity to study the microstructure development
with changes in either base glass composition or heat treatment conditions as well as to understand processing-microstructure-property
(mechanical/biological) relationship. In the present work, it is demonstrated how various crystal morphology can develop when
F− content in base glass (K2O–B2O3–Al2O3–SiO2–MgO–F) is varied in the range of 1.08–3.85% and when all are heat treated at varying temperatures of 1000–1120°C. For some
selected heat treatment temperature, the heat treatment time is also varied over 4–24 h. It was established that with increase
in fluoride content in the glass composition, the crystal volume fraction of the glass-ceramic decreases. Using 1.08% fluoride,
more than 80% crystal volume fraction could be achieved in the K2O–B2O3–Al2O3–SiO2–MgO–F system. It was observed that with lower fluoride content glass-ceramic, if heated at 1040°C for 12 h, an oriented microstructure
with ‘envelop like’ crystals can develop. For glass ceramics with higher fluorine content (2.83% or 3.85%), hexagonal-shaped
crystals are formed. Importantly, high hardness of around 8 GPa has been measured in glass ceramics with maximum amount of
crystals. The three-point flexural strength and elastic modulus of the glass-ceramic (heat treated at 1040°C for 24 h) was
80 MPa and 69 GPa of the sample containing 3.85% fluorine, whereas, similar properties obtained for the sample containing
1.08% F− was 94 MPa and 57 GPa, respectively. Further, in vitro dissolution study of the all three glass-ceramic composition in artificial
saliva (AS) revealed that leached fluoride ion concentration was 0.44 ppm, when the samples were immersed in AS for 8 weeks.
This was much lower than the WHO recommended safety limits of 1.5 ppm. Among all the investigated glass-ceramic samples, the
glass ceramic with 3.85% F− content in base glass (heat treated at 1040°C for 12 h), exhibits the adherence of Ca–P layer, which consists of spherical
particles of 2–3 μm. Other ions, such as Mg+2 and K+1 ion concentrations in the solution were found to be 8 and 315 ppm after 8 weeks of leaching, respectively. The leaching of
all metal ions is recorded to decrease with time, probably due to time-dependent kinetic modification of sample surface. Summarizing,
the present study illustrates that it is possible to obtain a good combination of crystallization, mechanical and in vitro
dissolution properties with the careful selection of base glass composition and heat treatment conditions. 相似文献
13.
Gladius Lewis Mark R. Towler Daniel Boyd Matthew J. German Anthony W. Wren Owen M. Clarkin Andrew Yates 《Journal of materials science. Materials in medicine》2010,21(1):59-66
Vertebroplasty (VP) and balloon kyphoplasty (BKP) are now widely used for treating patients in whom the pain due to vertebral
compression fractures is severe and has proved to be refractory to conservative treatment. These procedures involve percutaneous
delivery of a bolus of an injectable bone cement either directly to the fractured vertebral body, VB (VP) or to a void created
in it by an inflatable bone tamp (BKP). Thus, the cement is a vital component of both procedures. In the vast majority of
VPs and BKPs, a poly(methyl methacrylate) (PMMA) bone cement is used. This material has many shortcomings, notably lack of
bioactivity and very limited resorbability. Thus, there is room for alternative cements. We report here on two variants of
a novel, bioactive, Al-free, Zn-based glass polyalkenoate cement (Zn-GPC), and how their properties compare to those of an
injectable PMMA bone cement (SIMPL) that is widely used in VP and BKP. The properties determined were injectability, radiopacity,
uniaxial compressive strength, and biaxial flexural modulus. In addition, we compared the compression fatigue lives of a validated
synthetic osteoporotic VB model (a polyurethane foam cube with an 8 mm-diameter through-thickness cylindrical hole), at 0–2300 N
and 3 Hz, when the hole was filled with each of the three cements. A critical review of the results suggests that the performance
of each of the Zn-GPCs is comparable to that of SIMPL; thus, the former cements merit further study with a view to being alternatives
to an injectable PMMA cement for use in VP and BKP. 相似文献
14.
Synthesis of novel tricalcium phosphate-bioactive glass composite and functionalization with rhBMP-2
Schickle K Zurlinden K Bergmann C Lindner M Kirsten A Laub M Telle R Jennissen H Fischer H 《Journal of materials science. Materials in medicine》2011,22(4):763-771
A functionalization is required for calcium phosphate-based bone substitute materials to achieve an entire bone remodeling.
In this study it was hypothesized that a tailored composite of tricalcium phosphate and a bioactive glass can be loaded sufficiently
with rhBMP-2 for functionalization. A composite of 40 wt% tricalcium phosphate and 60 wt% bioactive glass resulted in two
crystalline phases, wollastonite and rhenanite after sintering. SEM analysis of the composite’s surface revealed a spongious
bone-like morphology after treatment with different acids. RhBMP-2 was immobilized non-covalently by treating with chrome
sulfuric acid (CSA) and 3-aminopropyltriethoxysilane (APS) and covalently by treating with CSA/APS, and additionally with
1,1′-carbonyldiimidazole. It was proved that samples containing non-covalently immobilized rhBMP-2 on the surface exhibit
significant biological activity in contrast to the samples with covalently bound protein on the surface. We conclude that
a tailored composite of tricalcium phosphate and bioactive glass can be loaded sufficiently with BMP-2. 相似文献
15.
Seok-Jung Hong Ishik Jeong Kyung-Tae Noh Hye-Sun Yu Gil-Su Lee Hae-Won Kim 《Journal of materials science. Materials in medicine》2009,20(9):1955-1962
The development of bioactive scaffolds with a designed pore configuration is of particular importance in bone tissue engineering.
In this study, bone scaffolds with a controlled pore structure and a bioactive composition were produced using a robotic dispensing
technique. A poly(ε-caprolactone) (PCL) and hydroxyapatite (HA) composite solution (PCL/HA = 1) was constructed into a 3-dimensional
(3D) porous scaffold by fiber deposition and layer-by-layer assembly using a computer-aided robocasting machine. The in vitro
tissue cell compatibility was examined using rat bone marrow stromal cells (rBMSCs). The adhesion and growth of cells onto
the robotic dispensed scaffolds were observed to be limited by applying the conventional cell seeding technique. However,
the initially adhered cells were viable on the scaffold surface. The alkaline phosphatase activity of the cells was significantly
higher on the HA–PCL than on the PCL and control culture dish, suggesting that the robotic dispensed HA–PCL scaffold should
stimulate the osteogenic differentiation of rBMSCs. Moreover, the expression of a series of bone-associated genes, including
alkaline phosphatase and collagen type I, was highly up-regulated on the HA–PCL scaffold as compared to that on the pure PCL
scaffold. Overall, the robotic dispensed HA–PCL is considered to find potential use as a bioactive 3D scaffold for bone tissue
engineering.
Seok-Jung Hong and Ishik Jeong contributed equally. 相似文献
16.
Ill Yong Kim Mark R. Towler Anthony Wren Chikara Ohtsuki 《Journal of materials science. Materials in medicine》2009,20(11):2267-2273
This study was concerned with the fabrication of ceramic CaO–SrO–ZnO–SiO2 spherical particles, which are novel candidates for the glass phase in glass polyalkenoate cements (GPCs). GPCs made from
these glasses have potential as bone cements because, unlike conventional GPCs, they do not contain aluminum ions, which inhibit
the calcification of hydroxyapatite in the body. The glass phase of GPCs require a controllable glass morphology and particle
size distribution. Sol–gel processing can potentially be used to fabricate homogenous ceramic particles with controlled morphology.
However, a thorough study on preparation conditions of spherical CaO–SrO–ZnO–SiO2 particles by sol–gel processing has, to date, not been reported. In this study, gels were prepared by hydrolysis and polycondensation
of tetraethoxysilane (TEOS) in an aqueous solution containing polyethylene glycol and nitrates of calcium, strontium and zinc.
It was possible to control the morphology and size of the gels by varying the H2O/TEOS molar ratio and the metal ion content in the starting compositions. An aliquot of 3–5 μm homogenous spherical particles
were obtained at a H2O/TEOS molar ratio of 42.6 when the starting composition molar ratios were Sr(NO3):Ca(NO3)2:Zn(NO3)2:Si(OC2H5)4 = x:0.12:(0.40 − x):0.48 (0 ≤ x ≤ 0.8). Starting composition limitations are caused by the low solubility of strontium ions
in the minimal amount of water used and the acceleration of hydrolysis as well as polycondensation at higher water content. 相似文献
17.
H. Lu T. Zhang X. P. Wang Q. F. Fang 《Journal of materials science. Materials in medicine》2009,20(3):793-798
Submicron bioactive glass fibers 70S30C (70 mol% SiO2, 30 mol% CaO) acting as bone tissue scaffolds were fabricated by electrospinning method. The scaffold is a hierarchical pore
network that consists of interconnected fibers with macropores and mesopores. The structure, morphological characterization
and mechanical properties of the submicron bioactive glass fibers were studied by XRD, EDS, FIIR, SEM, N2 gas absorption analyses and nanoindentation. The effect of the voltage on the morphology of electrospun bioactive glass fibers
was investigated. It was found that decreasing the applied voltage from 19 to 7 kV can facilitate the formation of finer fibers
with fewer bead defects. The hardness and Young’s modulus of submicron bioactive glass fibers were measured as 0.21 and 5.5 GPa,
respectively. Comparing with other bone tissue scaffolds measured by nanoindentation, the elastic modulus of the present scaffold
was relatively high and close to the bone. 相似文献
18.
Gülay Bayramoğlu Nilhan Kayaman-Apohan Handan Akçakaya Memet Vezir Kahraman Serap Erdem Kuruca Atilla Güngör 《Journal of materials science. Materials in medicine》2010,21(2):761-775
In this study a new branched methacrylated poly(propylene glycol-co-lactic acid) (PPG–PLA–IEM) and methacrylated cellulose
acetate butyrate resin (CAB–IEM) were synthesized. Hydrogels with various amounts of PPG–PLA–IEM and CAB–IEM (25, 50 and 75 wt%
IEM modified) were prepared by photopolymerization. Collagen tethered PEG–monoacrylate (PEGMA–collagen) was prepared and introduced
as a bioactive moiety to modify the hydrogel in order to enhance cell affinity. In vitro attachment and growth of 3T3 mouse
fibroblasts and human umbilical vein endothelial cells (HUVEC) on the hydrogels with and without collagen were also investigated.
It was observed that, the collagen improves the cell adhesion onto the hydrogel surface. With the increasing amount of collagen,
cell viability increased by 28% for ECV304 (P < 0.05) and 30% for 3T3 (P < 0.05). 相似文献
19.
Francesco Baino Enrica Verné Chiara Vitale-Brovarone 《Journal of materials science. Materials in medicine》2009,20(11):2189-2195
This research work aims to propose highly porous polymer/bioactive glass composites as potential scaffolds for hard-tissue
and soft-tissue engineering. The scaffolds were prepared by impregnating an open-cells polyurethane sponge with melt-derived
particles of a bioactive glass belonging to the SiO2–P2O5–CaO–MgO–Na2O–K2O system (CEL2). Both the starting materials and the composite scaffolds were investigated from a morphological and structural
viewpoint by X-ray diffraction analysis and scanning electron microscopy. Tensile mechanical tests, carried out according
to international ISO and ASTM standards, were performed by using properly tailored specimens. In vitro tests by soaking the
scaffolds in simulated body fluid (SBF) were also carried out to assess the bioactivity of the porous composites. It was found
that the composite scaffolds were highly bioactive as after 7 days of soaking in SBF a HA layer grew on their surface. The
obtained polyurethane/CEL2 composite scaffolds are promising candidates for tissue engineering applications. 相似文献
20.
Ruchi Mishra Bikramjit Basu Ashok Kumar 《Journal of materials science. Materials in medicine》2009,20(12):2493-2500
In the present work, biocomposite foams of bioactive glass along with polyvinyl alcohol and sodium alginate are designed and
developed as a potential biomaterial for bone regeneration. These biocomposite foams have a low density of 0.92 g/cm3, providing desired property for bone tissue engineering applications. Biocomposite foams were prepared via surfactant foaming.
Scanning electron microscopic characterization revealed pore size of 200–500 μm of the biocomposite foams. When these materials
were incubated in simulated body fluid, hydroxyapatite layer formation was observed on the material surface. To confirm the
cell viability and proliferation on these materials, MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay
was performed with NIH 3T3 fibroblast cells and the results revealed good biocompatibility with the biocomposite foams. Cell
adhesion studies further confirmed the biocompatibility of the scaffolds via cell attachment and ECM production. The optimally
synthesized biocomposite foams had a good combination of physical properties with compressive strength of 1.64 MPa and elastic
modulus of 18 MPa. In view of the favorable combination of physical and biological properties, the newly developed materials
are considered to be suitable for regeneration of trabecular bone. 相似文献