33 research outputs found
Effect of Micro- and Macroporosity of Bone Tissue Three-Dimensional-Poly(epsilon-Caprolactone) Scaffold on Human Mesenchymal Stem Cells Invasion, Proliferation, and Differentiation In Vitro
No full textThe design of porous scaffolds able to promote and guide cell proliferation, colonization, and biosynthesis in three dimensions is key determinant in bone tissue engineering (bTE). The aim of this study was to assess the role of the micro-architecture of poly(epsilon-caprolactone) scaffolds in affecting human mesenchymal stem cells' (hMSCs) spatial organization, proliferation, and osteogenic differentiation in vitro. Poly(epsilon-caprolactone) scaffolds for bTE and characterized by mono-modal and bi-modal pore size distributions were prepared by the combination of gas foaming and selective polymer extraction from co-continuous blends. The topological properties of the pore structure of the scaffolds were analyzed and the results correlated with the ability of hMSCs to proliferate, infiltrate, and differentiate in vitro in three dimensions. Results showed that the micro-architecture of the pore structure of the scaffolds plays a crucial role in defining cell seeding efficiency as well as hMSCs' three-dimensional colonization, proliferation, and osteogenic differentiation. Taken all together, our results indicated that process technologies able to allow a fine-tune of the topological properties of biodegradable porous scaffolds are essential for bTE strategies
The Effect of Thermoplastic Zein And Hydroxyapatite on the in vitro Degradation and Biological Response of Novel Multi-Phase PCL Scaffolds for Bone Tissue Engineering
No full textBiomineralized porous composite scaffolds prepared by chemical synthesis for bone tissue regeneration
No full textScaffold design is a key factor in the clinical success of bone tissue engineering grafts. To date, no existing single biomaterial used in bone repair and regeneration fulfils all the requirements for an ideal bone graft.
In this study hydroxyapatite/polycaprolactone (HA/PCL) composite scaffolds were prepared by a wet chemical method at room temperature. The physico-chemical properties of the composite materials were
characterized by X-ray diffraction, Fourier transform infrared spectroscopy and X-ray photoelectron
spectroscopy, while scaffold morphology was investigated by scanning electron microscopy (SEM) with
energy-dispersive spectroscopy to validate the process used for synthesis. Finally, the response of bone
marrow-derived human mesenchymal stem cells (hMSCs) in terms of cell proliferation and differentiation
to the osteoblastic phenotype was evaluated using the Alamar blue assay, SEM and alkaline phosphatase
activity. Microstructural analysis indicated that the HA particles were distributed homogeneously
within the PCL matrix. The biological results revealed that the HA/PCL composite scaffolds are suitable
for the proliferation and differentiation of MSCs in vitro, supporting osteogenesis after 15 days. All the
results indicate that these scaffolds meet the requirements of materials for bone tissue engineering
and could be used for many clinical applications in orthopaedic and maxillofacial surgery
Design of bimodal PCL and PCL-HA nanocomposite scaffolds by two step depressurization during solid-state supercritical CO2 foaming
No full textThis communication reports the design and fabrication of porous scaffolds of poly(e-capro- lactone) (PCL) and PCL loaded with hydroxyapatite (HA) nanoparticles with bimodal pore size distributions by a two step depressurization solid-state supercritical CO2 (scCO2) foaming process. Results show that the pore structure features of the scaffolds are strongly affected by the thermal history of the starting polymeric materials
and by the depressurization profile. In particular, PCL and PCL-HA nanocomposite scaffolds with bimodal and uniform pore size distributions are fabricated by quench- ing molten samples in liquid N2, solubilizing the scCO2 at 378C and 20MPa, and further releasing the blowing agent in two steps: (1) from 20 to 10MPa at a slow depressurization rate, and (2) from 10 MPa to the ambi- ent pressure at a fast depressurization rate. The biocom- patibility of the bimodal scaffolds is finally evaluated by the in vitro culture of human mesenchymal stem cells (MSCs), in order to assess their potential for tissue engin- eering applications
Effetto della Microstruttura Porosa di Scaffold di PCL sui Processi di Adesione, Colonizzazione, Proliferazione e Differenziamento di Cellule Staminali Mesenchimali in Vitro
No full textArchitecture and properties of bi-modal porous scaffolds for bone regeneration prepared via supercritical CO2 foaming and porogen leaching combined process
No full textThe aim of this study was the design of bi-modal porous scaffolds for bone tissue engineering (bTE) by combining supercritical CO2 (scCO2) foaming and porogen leaching techniques.
Poly(e-caprolactone) (PCL) was melt blended with thermoplastic zein (TZ) w/o the addition of 20 wt.% of HA particles to prepare a 40/60 (w/w) co-continuous blend and a 32/48/20 multi-phase composite, respectively. The materials were subsequently gas foamed by using scCO2 as blowing agent. Saturation and foaming temperatures and pressures, as well as depressurization time were selected in order to optimize the pore structure of the foams and, to induce the formation of a macro-porosity suitable for bone cell adhesion and colonization. The foams were subsequently soaked in water in order to leach out the plasticizer from the TZ phase and, to induce the formation of a bi-modal pore structure.
The effect of the composition of the materials and the foaming parameters on the properties of the scaffolds was assessed by SEM, image analyses and static compression tests. Furthermore, in vitro cell cultures were performed by using MG63 osteoblasts to assess the biocompatibility of the scaffolds and, to evaluate their capacity to promote cell adhesion, colonization and proliferation.
The results of this study demonstrated that the proposed technique allowed for the design and fabrication of bi-modal porous PCL/TZ and PCL/TZ-HA composite scaffolds by a green process. In particular, the scaffolds showed a 20–400 um macro-porosity, obtained by performing the scCO2 foaming process at a temperature higher than PCL melting, coupled with a 3 um micro-porosity, obtained by leaching out the plasticizer from the TZ phase. Finally, the biological characterization demonstrated that the scaf- folds allowed cell adhesion, colonization and proliferation up to 28 days of in vitro culture, therefore demonstrating potential for bTE
Microstructure, degradation and in vitro MG63 cells interactions of a new poly(ε-caprolactone), zein, and hydroxyapatite composite for bone tissue engineering
No full textNovel biodegradable biomaterials were investigated for potential application in bone tissue engineering. The biomaterials were prepared by blending poly(ε-caprolactone) and thermoplastic zein, a corn protein, with or without the incorporation of hydroxyapatite particles. The biomaterials were characterized in vitro to assess the degradation in phosphate buffer saline for 56 days by monitoring weight change, morphology, wettability, and tensile properties. The interaction between the biomaterials and MG63 was evaluated by proliferation, morphological characterization, and osteogenic differentiation assays up to 28 days in in vitro cultures. The incorporation of thermoplastic zein within poly(ε-caprolactone) enhanced the hydrophilicity and degradability, while minor effects were observed after the inclusion of the hydroxyapatite particles. Compared to the neat poly(ε-caprolactone), the multiphase poly(ε-caprolactone)/thermoplastic zein–hydroxyapatite composite improved the osteogenic differentiation of MG63 cells and is being considered a candidate material for bone tissue engineering application
Engineered μ-Bimodal Poly(ε -caprolactone) Porous Scaffold for Enhanced hMSCs Colonization and Proliferation
No full textThe use of scaffold-based strategies in the regeneration of biological tissues requires that the design of the microarchitecture of the scaffold satisfy key microstructural and biological requirements. Here, we examined the ability of a porous poly(e-caprolactone) (PCL) scaffold with novel bimodal-micron scale (l-bimodal) porous architecture to promote and guide the in vitro adhesion, proliferation and three-dimen- sional (3-D) colonization of human mesenchymal stem cells (hMSCs). The l-bimodal PCL scaffold was prepared by a combination of gas foaming (GF) and selective polymer extraction (PE) from co-continuous blends. The microarchitectural properties of the scaffold, in particular its morphology, porosity distribution and mechanical compression properties, were analyzed and correlated with the results of the in vitro cell–scaffold interaction study, carried out for 21 days under static conditions. Alamar Blue assay, scanning electron microscopy, confocal laser scanning microscopy and histological analyses were performed to assess hMSC adhesion, proliferation and 3-D colonization. The results showed that the combined GF–PE technique allowed the preparation of PCL scaffold with a unique multiscaled and highly inter- connected microarchitecture that was characterized by mechanical properties suitable for load-bearing applications. Study of the cell–scaf- fold interaction also demonstrated the ability of the scaffold to support hMSC adhesion and proliferation, as well as the possibility to promote and guide 3-D cell colonization by appropriately designing the microarchitectural features of the scaffold
Effect of micro- and macroporosity of bone tissue three-dimensional-poly(epsilon-caprolactone) scaffold on human mesenchymal stem cells invasion, proliferation, and differentiation in vitro
No full textThe design of porous scaffolds able to promote and guide cell proliferation, colonization, and biosynthesis in three dimensions is key determinant in bone tissue engineering (bTE). The aim of this study was to assess the role of the micro-architecture of poly(epsilon-caprolactone) scaffolds in affecting human mesenchymal stem cells' (hMSCs) spatial organization, proliferation, and osteogenic differentiation in vitro. Poly(epsilon-caprolactone) scaffolds for bTE and characterized by mono-modal and bi-modal pore size distributions were prepared by the combination of gas foaming and selective polymer extraction from co-continuous blends. The topological properties of the pore structure of the scaffolds were analyzed and the results correlated with the ability of hMSCs to proliferate, infiltrate, and differentiate in vitro in three dimensions. Results showed that the micro-architecture of the pore structure of the scaffolds plays a crucial role in defining cell seeding efficiency as well as hMSCs' three-dimensional colonization, proliferation, and osteogenic differentiation. Taken all together, our results indicated that process technologies able to allow a fine-tune of the topological properties of biodegradable porous scaffolds are essential for bTE strategies
