共查询到20条相似文献,搜索用时 31 毫秒
1.
Shen X Chen L Cai X Tong T Tong H Hu J 《Journal of materials science. Materials in medicine》2011,22(2):299-305
Homogeneous nanocomposites composed of hydroxyapatite (HAp) and collagen were synthesized using a novel in situ precipitation
method through dual template-driven. The morphological and componential properties of nanocomposites were investigated. The
HAp particulates, in sizes of about 50–100 nm, were distributed homogeneously in the organic collagen hydrogel. Highly magnified
TEM observation showed that HAp inorganic particles were composed of fine sub-particles (2–5 nm) without regular crystallographic
orientation. Based on these homogeneous nanocomposites, a novel HAp/collagen nanocomposite scaffold with hierarchical porosity
was prepared by multilevel freeze-drying technique. Compared to other conventional scaffolds for tissue engineering, this
novel in situ method endows synthesized composite scaffolds with unique morphology—ultrafine HAp particles dispersed homogenously
in collagen at nano level and the foam scaffold with hierarchical pore structures. The mechanical performance increased obviously
compared with neat collagen. These results provided an efficient approach toward new biomimetic tissue scaffold for the biomedical
applications with enhanced intensity/bioactivity and controlled resorption rates. This novel method, we expect, will lead
to a wide application in many other hydrogel systems and may be useful for fabrication of various homogeneous inorganic/organic
nanocomposites. 相似文献
2.
Huang J Li X Koller GP Di Silvio L Vargas-Reus MA Allaker RP 《Journal of materials science. Materials in medicine》2011,22(3):491-496
Nano-sized titanium containing hydroxyaptite has been prepared, the particle size of nanoTiHA was shown to be 12–20 nm in
width and 30–40 nm in length, smaller than that of nanoHA. X-ray diffraction analysis revealed the phase purity of nanoTiHA
produced. Antimicrobical assays demonstrated that nanoTiHA has excellent growth inhibitory properties, and is able to inhibit
the growth of all bacterial strains tested, both Gram-negative and Gram-positive species, including multi-antibiotic resistant
EMRSA 15 and EMRSA 16 ‘superbugs’. Biocidal activity against all four Staphylococcus spp was also shown at the concentration tested. Nanostuctured TiHA coating was successfully deposited onto Ti surfaces using
EHDA spraying under optimized processing conditions with the thickness of the coating being further controlled by the spraying
time. All of the nanoTiHA coated Ti surfaces were able to support human osteoblast (HOB) cell attachment and growth. The coating
thickness did not significantly influence the proliferation of HOB cells on nanoTiHA coatings, while the ability of nanoTiHA
coating to support HOB cell differentiation was demonstrated from the alkaline phosphatase activity. Our study showed that
nanoTiHA has excellent anti-bacterial properties and the thin nanoTiHA coating was also able to support the attachment, growth
and differentiation of HOB cells. Therefore, nanoTiHA coating could pave the way for the development of the next generation
of dental and orthopedic implants by offering anti-infection potential in addition to osteoconductivity. 相似文献
3.
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
4.
A. Rezaei M.R. Mohammadi 《Materials science & engineering. C, Materials for biological applications》2013,33(1):390-396
Hydroxyapatite (HA) is the most substantial mineral constituent of a bone which has been extensively used in medicine as implantable materials, owing to its good biocompatibility, bioactivity high osteoconductive, and/or osteoinductive properties. Nevertheless, its mechanical property is not utmost appropriate for a bone substitution. Therefore, a composite consist of HA and a biodegradable polymer is usually prepared to generate an apt bone scaffold. In the present work polycaprolactone (PCL), a newly remarkable biocompatible and biodegradable polymer, was employed as a matrix and hydroxyapatite nanoparticles were used as a reinforcement element of the composite. HA/PCL nanocomposites were synthesized by a new in situ sol–gel process using calcium hydroxide and phosphoric acid precursors in the presence of Tetrahydrofuran (THF) as a solvent. Chemical and physical characteristics of the nanocomposite were studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and Fourier transform infrared (FTIR) analyses. The results indicated that pure HA nanoparticles were well-incorporated and homogenously dispersed in the PCL matrix. It was found that the mechanical property of PCL was improved by addition of 20 wt.% HA nanoparticles. Furthermore, the biological property of nanocomposites was investigated under in vitro condition. For this purpose, HA/PCL scaffolds were prepared through a salt leaching process and immersed in a saturated simulated body fluid (SBF) after 3 and 7 days. It was found that a uniform layer of biomimetic HA could be deposited on the surface of HA/PCL scaffolds. Therefore, the prepared HA/PCL scaffolds showed good potential for bone tissue engineering and could be used for many clinical applications in orthopedic and maxillofacial surgery. 相似文献
5.
Li L Li G Jiang J Liu X Luo L Nan K 《Journal of materials science. Materials in medicine》2012,23(2):547-554
Development of fibrous scaffold of hydroxyapatite/biopolymer nanocomposite offers great potential in the field of bone regeneration
and tissue engineering. Hydroxyapatite (HA)/poly (ε-caprolactone) (PCL) fibrous scaffolds were successfully prepared by electrospinning
dopes containing HA and PCL in this work. It was found that pre-treating HA with γ-glycioxypropyltrimethoxysilane (A-187)
was effective in improving HA dispersion both in solutions and in a PCL matrix. Mechanical properties of the scaffolds were
greatly enhanced by the filling of A187-HA. The bioactivity of PCL was remarkably improved by the addition of HA and A187-HA.
Fibroblasts and osteoblasts were seeded on scaffolds to evaluate the effect of A-187 on biocompatibility of HA/PCL composites.
Based on this study, good dispersion of HA in PCL matrix was granted by pretreatment of HA with A-187 and A187-HA/PCL fibrous
scaffolds were obtained by electrospinning. These results demonstrated that the scaffolds may possess improved mechanical
performance and good bioactivity due to A187-HA incorporation. 相似文献
6.
Johari N Fathi MH Golozar MA Erfani E Samadikuchaksaraei A 《Journal of materials science. Materials in medicine》2012,23(3):763-770
In this study, biodegradation and biocompatibility of novel poly(ε-caparolactone)/nano fluoridated hydroxyapatite (PCL–FHA)
scaffolds were investigated. The FHA nanopowders were prepared via mechanical alloying method and had a chemical composition
of Ca10 (PO4)6OH2–x
F
x
(where x values were selected equal to 0.5 and 2.0). In order to fabricate PCL–FHA scaffolds, 10, 20, 30 and 40 wt% of the FHA were
added to the PCL. The PCL–FHA scaffolds were produced by the solvent casting/particulate leaching using sodium chloride particles
(with diameters of 300–500 μm) as the porogen. The phase structure, microstructure and morphology of the scaffolds were evaluated
using X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy techniques. Porosity of
the scaffolds was measured using the Archimedes’ Principle. In vitro degradation of PCL–FHA scaffolds was studied by incubating
the samples in phosphate buffered saline at 37°C and pH 7.4 for 30 days. Moreover, biocompatibility was evaluated by MTT assay
after seeding and culture of osteoblast-like cells on the scaffolds. Results showed that the osteoblast-like cells attached
to and proliferated on PCL–FHA and increasing the porosity of the scaffolds increased the cell viability. Also, degradation
rate of scaffolds were increased with increasing the fluorine content in scaffolds composition. 相似文献
7.
Electrospun bioactive nanocomposite scaffolds of polycaprolactone and nanohydroxyapatite for bone tissue engineering 总被引:3,自引:0,他引:3
Thomas V Jagani S Johnson K Jose MV Dean DR Vohra YK Nyairo E 《Journal of nanoscience and nanotechnology》2006,6(2):487-493
Nanocomposite scaffolds based on nanofibrous poly(epsilon-caprolactone) (PCL) and nanohydroxyapatite (nanoHA) with different compositions (wt%) were prepared by electrostatic co-spinning to mimic the nano-features of the natural extracellular matrix (ECM). NanoHA was found to be well dispersed in polymers up to the addition of 20 wt%, after ultrasonication. The composite scaffolds were characterized for structure and morphology using XRD, EDX, SEM, and DSC. The scaffolds have a porous nanofibrous morphology with fibers (majority) having diameters in the range of 450-650 nm, depending on composition, and interconnected pore structures. SEM, EDX, and XRD analyses have confirmed the presence of nanoHA in the fibers. As the nanoHA content in the fibers increases, the surface of fibers becomes rougher. The mechanical (tensile) property measurement of the electrospun composites reveals that as the nanoHA content increases, the ultimate strength increases from 1.68 MPa for pure PCL to 2.17, 2.65, 3.91, and 5.49 MPa for PCL/nanoHA composites with the addition of 5, 10, 15, and 20 wt% nanoHA, respectively. Similarly the tensile modulus also increases gradually from 6.12 MPa to 21.05 MPa with the increase of nanoHA content in the PCL/nanoHA fibers, revealing an increase in stiffness of the fibers due to the presence of HA. DSC analysis reveals that as nanoHA in the composite scaffolds increases, the melting point slightly increases due to the good dispersion and interface bonding between PCL and nanoHA. 相似文献
8.
Polycaprolactone (PCL), poly (lactic acid) (PLA) and hydroxyapatite (HA) are frequently used as materials for tissue engineering. In this study, PCL/PLA/HA nanofiber mats with different weight ratio were prepared using electrospinning. Their structure and morphology were studied by FTIR and FESEM. FTIR results demonstrated that the HA particles were successfully incorporated into the PCL/PLA nanofibers. The FESEM images showed that the surface of fibers became coarser with the introduction of HA nanoparticles into PCL/PLA system. Furthermore, the addition of HA led to the decreasing of fiber diameter. The average diameters of PCL/PLA/HA nanofiber were in the range of 300-600 nm, while that of PCL/PLA was 776 +/- 15.4 nm. The effect of nanofiber composition on the osteoblast-like MC3T3-E1 cell adhesion and proliferation were investigated as the preliminary biological evaluation of the scaffold. The MC3T3-E1 cell could be attached actively on all the scaffolds. The MTT assay revealed that PCL/PLA/HA scaffold shows significantly higher cell proliferation than PCL/PLA scaffolds. After 15 days of culture, mineral particles on the surface of the cells was appeared on PCL/PLA/HA nanofibers while normal cell spreading morphology on PCL/PLA nanofibers. These results manifested that electrospun PCL/PLA/HA scaffolds could enhance bone regeneration, showing their marvelous prospect as scaffolds for bone tissue engineering. 相似文献
9.
Falk Heinroth Dominic Gruss Sven Müller Florian Waltz Julia Martynczuk Armin Feldhoff Peter Behrens Michael Wiebcke 《Journal of Materials Science》2010,45(6):1595-1603
Having new potential applications in forging processes in mind, composites of an ordered mesoporous carbon and luminescent
metal phosphate nanocrystals were synthesized for the first time. Three kinds of CMK-3/CePO4:Tb nanocomposites were prepared by treating a mesoporous CMK-3 host with different lanthanide phosphate precursor solutions.
Characterization of the obtained nanocomposites by small-angle X-ray scattering, wide-angle X-ray diffraction, transmission
electron microscopy, thermogravimetry, and nitrogen physisorption analysis showed that in two cases, the nanocrystals (ca.
2–3 nm in size) were located inside the mesopores, whereas in the third case the nanocystals (ca. 6 nm in size) merely adhered
to the outer surfaces of the carbon particles. The CMK-3 and the two nanocomposites had ordered hexagonal structures (space
group p6mm); all the materials possessed amorphous carbon walls. After combustion of the nanocomposites, the residues upon excitation
with UV light exhibited the typical green luminescence of Tb3+. A preliminary evaluation of the lubrication properties of the CMK-3 and one nanocomposite material was performed. The friction
factors determined by means of ring upsetting tests revealed that the carbon materials were able to lower frictional forces
although they were 3–4 times less efficient than a commercial graphite-based reference lubricant. 相似文献
10.
Koh YH Bae CJ Sun JJ Jun IK Kim HE 《Journal of materials science. Materials in medicine》2006,17(9):773-778
A combination of bi-axial machining and lamination was used to fabricate macrochanneled poly (ɛ-caprolactone) (PCL)/hydroxyapatite
(HA) scaffolds. Thermoplastic PCL/HA sheets with a thickness of 1 mm, consisting of a 40 wt% PCL polymer and 60 wt% HA particles,
were bi-axially machined. The thermoplastic PCL/HA exhibited an excellent surface finish with negligible tearing of the PCL
polymer and pull-out of the HA particles. The bi-axially machined sheets were laminated with a solvent to give permanent bonding
between the lamina. This novel process produced three-directionally connected macrochannels in the dense PCL/HA body. The
macrochanneled PCL/HA scaffold exhibited excellent ductility and reasonably high strength. In addition, good cellular responses
were observed due to the osteoconductive HA particles. 相似文献
11.
Liang Ye Xinchen Zeng Haojiang Li Yi Ai 《Journal of materials science. Materials in medicine》2010,21(2):753-760
Nano biocomposite scaffolds of non-stoichiometric apatite (ns-AP) and poly(ε-caprolactone) (PCL) were prepared by a prototyping
controlled process (PCP). The results show that the composite scaffolds with 40 wt% ns-AP contained open and well interconnected
pores with a size of 400–500 μm, and exhibited a maximum porosity of 76%. The ns-AP particles were not completely embedded
in PCL matrix while exposed on the composite surface, which might be useful for cell attachment and growth. Proliferation
of MG63 cells was significantly better on the composite scaffolds with porosity of 76% than that those with porosity of 53%, indicating
that the scaffolds with high porosity facilitated cell growth, and could promote cell proliferation. The composite scaffolds
were implanted into rabbit thighbone defects to investigate the in vivo biocompatibility and osteogenesis. Radiological and
histological examination confirmed that the new bony tissue had grown easily into the entire composite scaffold. The results
suggest that the well-interconnected pores in the scaffolds might encourage cell proliferation, and migration to stimulate
cell functions, thus enhancing bone formation in the scaffolds. This study shows that bioactive and biocompatible ns-AP/PCL
composite scaffolds have potential applications in bone tissue engineering. 相似文献
12.
Sanjukta Deb Ramin Mandegaran Lucy Di Silvio 《Journal of materials science. Materials in medicine》2010,21(3):893-905
One of the major factors in the therapeutic success of bone tissue engineered scaffolds is the ability of the construct to
vascularise post implantation. One of the approaches for improving vascularisation within scaffolds has been to co-culture
human umbilical vein endothelial cells (HUVECS) with human osteoblasts (HOBS), which may then promote vascularisation and
facilitate tissue regeneration. However, in order to mimic a natural physiological niche it is vital that the scaffold is
able to support and promote the proliferation of both cell types and thus become a viable tissue engineered construct. In
this study we report the development of a porous bioactive glass–ceramic construct and examine the interaction with human
umbilical vein endothelial cells (HUVEC’s) and human osteoblast-like cell both in mono and co-culture. The study clearly demonstrated
that the scaffolds were able to support both endothelial and human osteoblast cell proliferation both in mono and co-culture.
A comparison of the proliferation response of HUVEC and HOB in mono-culture on the test scaffolds and the commercial porous
hydroxyapatite was assessed over a 28 day period (4, 7, 14, 21 and 28 days), using alamar BlueTM assay. Proliferation of HOB cells seeded in the scaffolds was consistently shown to be above those observed on commercial
HA scaffolds. 相似文献
13.
Chen J Luo Y Hong L Ling Y Pang J Fang Y Wei K Gao X 《Journal of materials science. Materials in medicine》2011,22(3):547-555
A superior drug controlled release system capable of achieving efficient osteogenesis is in imperative demand because of limited
bone substitute tissue for the treatment of bone defect. In the present study, we investigated the potential of using poly(ε-caprolactone)–hydroxyapatite
(PCL–HA) composite microspheres as an injectable bone repair vehicle by controlled release of alendronate (AL), a medicine
that belongs to the bisphosphonates family. The PCL/HA–AL microspheres were prepared with solid/oil/water emulsion technique,
which included two processes: (1) AL was loaded on the hydroxyapatite nanoparticles; (2) the HA–AL complex was built in the
PCL matrix. The spherical PCL/HA–AL microspheres were characterized with its significantly improved encapsulation efficiency
of hydrophilic AL and better sustained release. Human bone mesenchymal stem cells (hMSCs) were cultured on the surface of
these microspheres and exhibited high proliferative profile. Specifically, in osteogenic medium, hMSCs on the surface of PCL/HA–AL
microspheres displayed superior osteogenic differentiation which was verified by alkaline phosphatase activity assay. In conclusion,
by presenting strong osteogenic commitment of hMSCs in vitro, the PCL/HA–AL microspheres have the potential to be used as
an injectable vehicle for local therapy of bone defect. 相似文献
14.
Houmard M Fu Q Saiz E Tomsia AP 《Journal of materials science. Materials in medicine》2012,23(4):921-930
Highly porous calcium phosphate (CaP) scaffolds for bone-tissue engineering were fabricated by combining a robocasting process
with a sol–gel synthesis that mixed Calcium Nitrate Tetrahydrate and Triethyl Phosphite precursors in an aqueous medium. The
resulting gels were used to print scaffolds by robocasting without the use of binder to increase the viscosity of the paste.
X-ray diffraction analysis confirmed that the process yielded hydroxyapatite and β-tricalcium phosphate biphasic composite
powders. Thus, the scaffold composition after crystallization of the amorphous structure could be easily modified by varying
the initial Ca/P ratio during synthesis. The compressive strengths of the scaffolds are ~6 MPa, which is in the range of human
cancellous bone (2–12 MPa). These highly porous scaffolds (~73 vol% porosity) are composed of macro-pores of ~260 μm in size;
such porosity is expected to enable bone ingrowth into the scaffold for bone repair applications. The chemistry, porosity,
and surface topography of such scaffolds can also be modified by the process parameters to favor bone formation. The studied
sol–gel process can be used to coat these scaffolds by dip-coating, which induces a significant enhancement of mechanical
properties. This can adjust scaffold properties such as composition and surface morphology, which consequently may improve
their performances. 相似文献
15.
Wen He Zhengmao Li Yingjun Wang Xiaofeng Chen Xudong Zhang Hongshi Zhao Shunpu Yan Weijia Zhou 《Journal of materials science. Materials in medicine》2010,21(1):155-159
In this study, hydroxyapatite (HAp) particles with mesoporous structure have been synthesized from calcium hydroxide and di-ammonium
hydrogen phosphate using yeast cells as the template. The characterization methods such as X-ray diffraction (XRD), Fourier
transform infrared spectrograph (FTIR), N2 adsorption–desorption isotherms (NADI), transmission electron microscopy (TEM) and field emission scanning electron microscopy
(FESEM) were used for determination of the particles structure (particle size, structural evolution and morphology). The results
show that HAp particles with mesoporous structure could be produced. The size of HAp particles was approximately hundreds
of nanometer. The pore width of HAp particles was in the range of 2.0–40 nm and the maximum centered around 4.5 nm. 相似文献
16.
Paola Fabbri Federica Bondioli Massimo Messori Cristina Bartoli Dinuccio Dinucci Federica Chiellini 《Journal of materials science. Materials in medicine》2010,21(1):343-351
Polycaprolactone/hydroxyapatite (PCL/HA) composites were prepared by in situ generation of HA in the polymer solution starting
from the precursors calcium nitrate tetrahydrate and ammonium dihydrogen phosphate via sol–gel process. Highly interconnected
porosity was achieved by means of the salt-leaching technique using a mixture of sodium chloride and sodium bicarbonate as
porogens. Structure and morphology of the PCL/HA composites were investigated by scanning electron microscopy, and mechanical
properties were determined by means of tensile and compression tests. The possibility to employ the developed composites as
scaffolds for bone tissue regeneration was assessed by cytotoxicity test of the PCL/HA composites extracts and cell adhesion
and proliferation in vitro studies. 相似文献
17.
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
18.
Amit K. Jaiswal Hemlata Chhabra Sachin S. Kadam Kishore Londhe Vivek P. Soni Jayesh R. Bellare 《Materials science & engineering. C, Materials for biological applications》2013,33(5):2926-2936
The aim of this study was to compare physico-chemical and biological properties of hydroxyapatite (HA) and hardystonite (HS) based composite scaffolds. Hardystonite (Ca2ZnSi2O7) powders were synthesized by a sol–gel method while polycaprolactone–hardystonite (PCL–HS) and polycaprolactone–hydroxyapatite (PCL–HA) were fabricated in nanofibrous form by electrospinning. The physico-chemical and biological properties such as tensile strength, cell proliferation, cell infiltration and alkaline phosphatase activity were determined on both kinds of scaffolds. We found that PCL–HS scaffolds had better mechanical strength compared to PCL–HA scaffolds. Addition of HA and HS particles to PCL did not show any inhibitory effect on blood biocompatibility of scaffolds when assessed by hemolysis assay. The in vitro cellular behavior was evaluated by growing murine adipose-tissue-derived stem cells (mE-ASCs) over the scaffolds. Enhanced cell proliferation and improved cellular infiltrations on PCL–HS scaffolds were observed when compared to HA containing scaffolds. PCL–HS scaffolds exhibited a significant increase in alkaline phosphatase (ALP) activity and better mineralization of the matrix in comparison to PCL–HA scaffolds. These results clearly demonstrate the stimulatory role of Zn and Si present in HS based composite scaffolds, suggesting their potential application for bone tissue engineering. 相似文献
19.
Huang J Jayasinghe SN Best SM Edirisinghe MJ Brooks RA Rushton N Bonfield W 《Journal of materials science. Materials in medicine》2005,16(12):1137-1142
Suspensions containing nano-sized silicon substituted hydroxyaptite (nSiHA) particles were produced and processed for electrostatic
spray deposition. No secondary phases were detected by X-ray diffraction, which indicated that the nSiHA was phase pure. Electrostatic
spraying of nSiHA in cone-jet mode was achieved at flow rate of 10−9 m3s−1 with an applied voltage between the needle and the ring-shaped ground electrode set at 6 to 8 kV. Micrometer- and submicrometer-scaled
islands of nSiHA have been deposited on glass and titanium substrates. The surface roughness of such nHA and nSiHA islands
was in the range 60 to 80 nm, as measured from atomic force microscopy in tapping mode. The growth of primary human osteoblast
(HOB) cells on the nSiHA deposited substrates increased with time during the 4 days of culture, and the increase was related
with the Si content in substituted HA, indicating that nSiHA was able to promote and support the growth of HOB cells. Scanning
electron microscopy (SEM) revealed that extracellular matrix (ECM) produced by the HOB cells on these nSiHA deposits was well
organized. In addition, the presence of Ca and P containing nodules in the ECM were also confirmed by Energy Dispersive X-ray
(EDX) analysis, indicating early signs of calcification fronts. The results showed that nSiHA produced by electrostatic spray
deposition was able to promote the attachment and the growth of HOB cells. Therefore, electrostatic spray deposition offers
great potential for the creation of bioactive surfaces to provide improved interfacial bonding with host tissues. 相似文献
20.
Here we produced macroporous and nanofibrous scaffolds with bioactive nanocomposite composition, poly(lactic acid) (PLA) incorporating bioactive glass nanoparticles (BGnp) up to 30 wt%, targeting bone regeneration. In particular, the nanofibrous structure in the scaffolds was generated by using a bicyclic monoterpene, camphene (C10H16), through a phase-separation process with PLA-BGnp phase in chloroform/1,4-dioxane co-solvent. Furthermore, macropores were produced by the impregnation of salt particles and their subsequent leaching out, followed by freezing and lyophilization processes. The produced PLA-BGnp scaffolds presented highly porous and nanofibrous structure with porosities of 90–95% and pore sizes of over hundreds of micrometers. BGnp with sizes of ∼90 nm were also evenly impregnated within the PLA matrix, featuring a nanocomposite structure. The nanofibrous scaffolds exhibited enhanced hydrophilicity and more rapid hydrolytic degradation as the incorporated BGnp content increased. The bone-bioactivity of the scaffolds was substantially improved with the incorporation of BGnp, exhibiting rapid formation of apatite throughout the scaffolds in a simulated body fluid. The developed macroporous and nanofibrous scaffolds with PLA-BGnp bioactive composition are considered as a novel 3D matrix potentially useful for bone tissue engineering. 相似文献