References of "Maquet, Véronique"
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See detailPoly (D,L-lactic acid) macroporous guidance scaffolds seeded with Schwann cells genetically modified to secrete bi-functional neurotrophin implanted in the completely transected adult rat thoracic spinal cord
Hurtado, Andres; Moon, Lawrence D F; Maquet, Véronique et al

in Biomaterials (2006), 27(3), 430-442

Freeze-dried poly(D,L-lactic acid) macroporous scaffold filled with a fibrin solution containing Schwann cells (SCs) lentivirally transduced to produce and secrete D15A, a bi-functional neurotrophin with ... [more ▼]

Freeze-dried poly(D,L-lactic acid) macroporous scaffold filled with a fibrin solution containing Schwann cells (SCs) lentivirally transduced to produce and secrete D15A, a bi-functional neurotrophin with brain-derived neurotrophic factor and neurotrophin-3 activity, and to express green fluorescent protein (GFP) were implanted in the completely transected adult rat thoracic spinal cord. Control rats were similarly injured and then implanted with scaffolds containing the fibrin solution with SCs lentivirally transduced to produce express GFP only or with the fibrin solution only. Transgene production and biological activity in vitro, SC survival within the scaffold in vitro and in vivo, scaffold integration, axonal regeneration and myelination, and hind limb motor function were analyzed at 1, 2, and 6 weeks after implantation. In vitro, lentivirally transduced SCs produced 87.5 ng/24 h/10(6) Cells of D15A as measured by neurotrophin-3 activity in ELISA. The secreted D15A was biologically active as evidenced by its promotion of neurite outgrowth of dorsal root ganglion neurons in culture. In vitro, SCs expressing GFP were present in the scaffolds for up to 6 It, the end of a typical surgery session. Implantation of SC-seeded scaffolds caused modest loss of spinal nervous tissue. Reactive astrocytes and chondroitin sulfate glycosaminoglycans were present in spinal tissue adjacent to the scaffold. Vascularization of the scaffold was ongoing at I week post-implantation. There were no apparent differences in scaffold integration and blood vessel formation between groups. A decreasing number of implanted (GFP-positive) SCs were found within the scaffold during the first 3 days after implantation. Apoptosis was identified as one of the mechanisms of cell death. At 1 week and later time points after implantation, few of the implanted SCs were present in the scaffold. Neurofilament-positive axons were found in the scaffold. At 6 weeks post-grafting, myelinated axons were observed within and at the external surface of the scaffold. Axons did not grow from the scaffold into the caudal cord. All groups demonstrated a similar improvement of hind limb motor function. Our findings demonstrated that few seeded SCs survived in vivo, which could account for the modest axonal regeneration response into and across the scaffold. For the development of SC-seeded macroporous scaffolds that effectively promote axonal regeneration in the injured spinal cord, the survival and/or total number of SCs in the scaffold needs to be improved. (c) 2005 Elsevier Ltd. All rights reserved. [less ▲]

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See detailIn vitro and in vivo analysis of macroporous biodegradable poly(D,L-lactide-co-glycolide) scaffolds containing bioactive glass
Day, Richard M; Maquet, Véronique; Boccaccini, Aldo R. et al

in Journal of Biomedical Materials Research, Part A (2005), 75A(4), 778-787

Recent studies have demonstrated the angiogenic potential of 45S5 Bioglass (R). However, it is not known whether the angiogenic properties of Bioglass (R) remain when the bioactive glass particles are ... [more ▼]

Recent studies have demonstrated the angiogenic potential of 45S5 Bioglass (R). However, it is not known whether the angiogenic properties of Bioglass (R) remain when the bioactive glass particles are incorporated into polymer composites. The objectives of the current study were to investigate the angiogenic properties of 45S5 Bioglass (R) particles incorporated into biodegradable polymer composites. In vitro studies demonstrated that fibroblasts Cultured on discs consisting of specific quantities of Bioglass (R) particles mixed into poly(D,L-lactide-co-glycolide) secreted significantly increased quantities of vascular endothelial growth factor. The optimal quantity of Bioglass (R) particles determined from the in vitro experiments was incorporated into three-dimensional macroporous poly(D,L-lactide-co-glycolide) foam scaffolds. The foam scaffolds were fabricated using either compression molding or thermally induced phase separation processes. The foams were implanted subcutaneously into mice for periods Of Lip to 6 weeks. Histological assessment was used to determine the area of granulation tissue around the foams, and the number of blood vessels within the granulation tissue was counted. The presence of Bioglass (R) particles in the foams produced a sustained increase in the area of granulation tissue surrounding the foams. The number of blood vessels surrounding the neat foams was reduced after 2 weeks of implantation; however, compression-molded foams containing Bioglass (R) after 4 and 6 weeks of implantation had significant]), more blood vessels surrounding the foams compared with foams containing no Bioglass (R) at the same time points. These results indicate that composite polymer foam scaffolds containing Bioglass (R) particles retain granulation tissue and blood vessels surrounding the implanted foams. The use of this polymer composite for tissue engineering scaffolds might provide a novel approach for ensuring adequate vascular Supply to the implanted device. [less ▲]

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See detailMechanical properties of highly porous PDLLA/Bioglass (R) composite foams as scaffolds for bone tissue engineering
Blaker, Jonny J.; Maquet, Véronique; Jérôme, Robert ULg et al

in Acta Biomaterialia (2005), 1(6), 643-652

This study developed highly porous degradable composites as potential scaffolds for bone tissue engineering. These scaffolds consisted of poly-d,l-lactic acid filled with 2 and 15 vol.% of 45S5 Bioglass® ... [more ▼]

This study developed highly porous degradable composites as potential scaffolds for bone tissue engineering. These scaffolds consisted of poly-d,l-lactic acid filled with 2 and 15 vol.% of 45S5 Bioglass® particles and were produced via thermally induced solid–liquid phase separation and subsequent solvent sublimation. The scaffolds had a bimodal and anisotropic pore structure, with tubular macro-pores of 100 μm in diameter, and with interconnected micro-pores of 10–50 μm in diameter. Quasi-static and thermal dynamic mechanical analysis carried out in compression along with thermogravimetric analysis was used to investigate the effect of Bioglass® on the properties of the foams. Quasi-static compression testing demonstrated mechanical anisotropy concomitant with the direction of the macro-pores. An analytical modelling approach was applied, which demonstrated that the presence of Bioglass® did not significantly alter the porous architecture of these foams and reflected the mechanical anisotropy which was congruent with the scanning electron microscopy investigation. This study found that the Ishai–Cohen and Gibson–Ashby models can be combined to predict the compressive modulus of the composite foams. The modulus and density of these complex foams are related by a power-law function with an exponent between 2 and 3. [less ▲]

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See detailAnalyse quantitative de la texture poreuse d'un matériau polymère cellulaire basée sur des images de microtomographie à rayons X
Lecocq, Raphaël; Toye, Dominique ULg; Maquet, Véronique et al

Poster (2005, October)

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See detailÉtude de la texture poreuse d'un matériau polymère cellulaire utilisé en ingénierie tissulaire par microtomographie à rayons X
Lecocq, Raphaël; Toye, Dominique ULg; Maquet, Véronique et al

Poster (2005, October)

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See detailStudy of the connectivity properties of Bioglass®-filled polylactide foam scaffolds by image analysis and impedance spectroscopy
Blacher, Silvia ULg; Maquet, Véronique; Jérôme, Robert ULg et al

in Acta Biomaterialia (2005), 1(5), 565-574

The porous structure of two series of poly(d,l-lactide)/Bioglass® composite foams prepared by thermal-induced phase separation was investigated by image analysis and impedance spectroscopy. Polymer ... [more ▼]

The porous structure of two series of poly(d,l-lactide)/Bioglass® composite foams prepared by thermal-induced phase separation was investigated by image analysis and impedance spectroscopy. Polymer solutions of either low or high molecular weight containing different concentrations (up to 50 wt.%) of Bioglass® particles of mean particle size d < 5 µm were studied. The morphology of both macro- and micropores was studied by scanning electron microscopy and image analysis of both neat and composite foams (containing 10-50 wt.% Bioglass®). The pore connectivity of both neat polymer and composite foams was characterized by impedance spectroscopy in relation with their transport properties. The influence of the foam composition (i.e., polymer molecular weight and concentration of Bioglass®) on pore microstructure was studied using these non-destructive methods. It was found that addition of Bioglass® particles has a pronounced effect on pore orientation, leading to increasing loss of order of pore structure, especially for low-molecular weight PDLLA foams. [less ▲]

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See detailSynthesis and characterization of electrically conducting polyester foams
Maquet, Véronique; Gabriel, Sabine ULg; Garrais, Solange et al

Poster (2005, June 01)

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See detailSynthesis and characterization of electrically conducting polyester/MWNTs nanocomposite foams
Garrais, Solange; Maquet, Véronique; Jérôme, Christine ULg et al

Poster (2005, June 01)

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See detailWetting of bioactive glass surfaces by poly(alpha-hydroxyacid) melts: interaction between Bioglass (R) and biodegradable polymers
Blaker, Jonny J.; Maquet, Véronique; Boccaccini, Aldo R. et al

in e-Polymers (2005), 23

The interfacial characteristics between bioactive glass (4555 Bioglass(R)) surfaces and poly(alpha-hydroxyacid) melts have been assessed by direct wetting measurements. In particular, the wettability of ... [more ▼]

The interfacial characteristics between bioactive glass (4555 Bioglass(R)) surfaces and poly(alpha-hydroxyacid) melts have been assessed by direct wetting measurements. In particular, the wettability of Bioglass(R) powder by poly(D,L-lactide) (PDLLA) and poly(D,L-lactide-co-glycolide) (PLGA) was assessed by imbibition measurements. Additionally, the equilibrium contact angles of PDLLA and PLGA melts on a sintered Bioglass(R) surface were measured. The surface energy of the bioactive glass and the polymers was determined from contact angles measured using various test liquids on PDLLA, PLGA and Bioglass(R) solid substrates. There are sufficient adhesive interactions between the polymers and Bioglass(R). A simple heat treatment of the bioactive glass in an inert gas atmosphere leads to an improved wetting behaviour, indicating increased adhesive interactions. Scanning electron micrographs of the polymer+Bioglass(R) composites formed by polymer penetration into the powder bed show the formation of a 'good quality' interface. [less ▲]

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See detailPreparation and characterisation of poly(lactide-co-glycolide) (PLGA) and PLGA/Bioglass((R)) composite tubular foam scaffolds for tissue engineering applications
Boccaccini, Aldo R.; Blaker, Jonny J.; Maquet, Véronique et al

in Materials Science and Engineering C: Biomimetic and Supramolecular Systems (2005), 25(1), 23-31

Polylactide-co-glycolide (PLGA) and PLGA/Bioglass(R) foams of tubular shape have been prepared with a 1 wt% 45S5 Bioglass(R) content. Porous membranes with varying thickness and porosity were fabricated ... [more ▼]

Polylactide-co-glycolide (PLGA) and PLGA/Bioglass(R) foams of tubular shape have been prepared with a 1 wt% 45S5 Bioglass(R) content. Porous membranes with varying thickness and porosity were fabricated via a thermally induced phase separation process from which tubes of controlled diameter and wall thickness in the range 1.5-3 mm were produced. Scanning electron microscopy (SEM) revealed that the structure of the tubular foams consisted of radially oriented and highly interconnected pores with two distinct pore sizes, i.e. macropores similar to100-mum average diameter and interconnected micropores of 10-50-mum diameter. Foams with Bioglass(R) inclusions showed similarly well-defined tubular and interconnected pore morphology. Cell culture studies using mouse fibroblasts (L929) were conducted to assess the biocompatibility of the scaffolds in vitro. L929 fibroblasts cultured in medium that was pre-conditioned by incubating with PLGA tubes containing Bioglass(R) had a significant reduction in cell proliferation compared with fibroblasts grown in unconditioned medium (P < 0.0001). The PLGA and PLGA/Bioglass(R) tubular foams developed here are candidate materials for soft-tissue engineering scaffolds. holding promise for the regeneration of tissues requiring a tubular shape scaffold. such as intestine. trachea and blood vessels. [less ▲]

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See detailProcess for depositing strong adherend polymer coating onto an electrically conductive surface
Bertrand, Olivier; Jérôme, Robert ULg; Gautier, Sandrine et al

Patent (2004)

Process for depositing by electrografting a strong adherent polymer coating onto an electrically conductive surface comprising an electrochemical grafting at the surface of an active monomer for forming a ... [more ▼]

Process for depositing by electrografting a strong adherent polymer coating onto an electrically conductive surface comprising an electrochemical grafting at the surface of an active monomer for forming a primer coating P onto said surface and having as general formula: X0 (meth)acrylate wherein X is either part of a preformed polymer or is an intermediate agent for polyaddition reaction or is an anchoring group for attachment of a molecule having at least one complementary reactive group. Such process allows formation of new primer by one-step electro-grafting of a reactive polymer called macromonomer.; Such process also allows further modification of an initial electrografted polymer (called primer coating) to increase the coating thickness by the so-called grafting-from technique i.e. polymerization of a second monomer or to introduce other types of polymers(also called top coating) via covalent attachment between the primer and the top coating through the X ester group by the so called grafting onto technique. Such process also allows to graft onto the primer coating compounds like functional polymer, peptide, protein, oligonucleotide, dyes, drugs, anti-bacterian compounds. [less ▲]

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See detailPorous poly(α-hydroxyacid)/Bioglass® composite scaffolds for bone tissue engineering. I: preparation and in vitro characterisation
Maquet, Véronique; Boccaccini, Aldo R.; Pravata, Laurent et al

in Biomaterials (2004), 25(18), 4185-4194

Highly porous composites scaffolds of poly-D,L-lactide (PDLLA) and poly(lactide-co-glycolide) (PLGA) containing different amounts (10, 25 and 50wt%) of bioactive glass (45S5 bioglass®) were prepared by ... [more ▼]

Highly porous composites scaffolds of poly-D,L-lactide (PDLLA) and poly(lactide-co-glycolide) (PLGA) containing different amounts (10, 25 and 50wt%) of bioactive glass (45S5 bioglass®) were prepared by thermally induced solid-liquid phase separation (TIPS) and subsequent solvent sublimation. The addition of increasing amounts of bioglass® into the polymer foams decreased the pore volume. Conversely, the mechanical properties of the polymer materials were improved. The composites were incubated in phosphate buffer saline at 37°C to study the in vitro degradation of the polymer by measurement of water absorption, weight loss as well as changes in the average molecular weight of the polymer and in the pH of the incubation medium as a function of the incubation time. The addition of bioglass®to polymer foams increased the water absorption and weight loss compared to neat polymer foams. However, the polymer molecular weight, determined by size exclusion chromatography, was found to decrease more rapidly and to a larger extent in absence of bioglass®. The presence of the bioactive filler was therefore found to delay the degradation rate of the polymer as compared to the neat polymer foams. Formation of hydroxyapatite on the surface of composites, as an indication of their bioactivity, was recorded by EDXA, X-ray diffractometry and confirmed by Raman spectroscopy. [less ▲]

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See detailProcess for depositing strong adherend polymer coating onto an electrically conductive surface
Bertrand, Olivier; Jérôme, Robert ULg; Gautier, Sandrine et al

Patent (2004)

Process for depositing by electrografting a strong adherent polymer coating onto an electrically conductive surface comprising the step of electrochemical grafting of an active monomer for forming a ... [more ▼]

Process for depositing by electrografting a strong adherent polymer coating onto an electrically conductive surface comprising the step of electrochemical grafting of an active monomer for forming a primer coating P onto the surface and having as general formula: X0 (meth)acrylate wherein X is either part of a preformed polymer or is an intermediate agent for polyaddition reaction or is an anchoring group for attachment of a molecule having at least one complementary reactive group. Such process allows formation of new primer by one-step electro-grafting of a macromonomer. Such process also allows further modification of an initial electrografted polymer to increase the coating thickness by the grafting-from technique. Such process also allows to graft onto the primer coating compounds like functional polymer, peptide, protein, oligonucleotide, dyes, drugs, anti-bacterian compounds. [less ▲]

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See detailProcess for depositing strong adherend polymer coating onto an electrically conductive surface
Bertrand, Oliver; Jérôme, Robert ULg; Gautier, Sandrine et al

Patent (2004)

Process for depositing by electrografting a strong adherent polymer coating onto an electrically conductive surface comprising an electrochemical grafting at the surface of an active monomer for forming a ... [more ▼]

Process for depositing by electrografting a strong adherent polymer coating onto an electrically conductive surface comprising an electrochemical grafting at the surface of an active monomer for forming a primer coating P onto said surface and having as general formula: X0 (meth)acrylate wherein X is either part of a preformed polymer or is an intermediate agent for polyaddition reaction or is an anchoring group for attachment of a molecule having at least one complementary reactive group. Such process allows formation of new primer by one-step electro-grafting of a reactive polymer called macromonomer.; Such process also allows further modification of an initial electrografted polymer (called primer coating) to increase the coating thickness by the so-called grafting-from technique i.e. polymerization of a second monomer or to introduce other types of polymers(also called top coating) via covalent attachment between the primer and the top coating through the X ester group by the so called grafting onto technique. Such process also allows to graft onto the primer coating compounds like functional polymer, peptide, protein, oligonucleotide, dyes, drugs, anti-bacterian compounds. [less ▲]

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See detailIn vivo characterisation of a novel bioresorbable poly(lactide-co-glycolide) tubular foam scaffold for tissue engineering applications
Day, Richard M; Boccaccini, Aldo R.; Maquet, Véronique et al

in Journal of Materials Science: Materials in Medicine (2004), 15(6), 729-734

Polylactide-co-glycolide (PLGA) foams of tubular shape were assessed for their use as soft-tissue engineering scaffolds in vitro and in vivo. Porous membranes were fabricated by a thermally induced phase ... [more ▼]

Polylactide-co-glycolide (PLGA) foams of tubular shape were assessed for their use as soft-tissue engineering scaffolds in vitro and in vivo. Porous membranes were fabricated by a thermally induced phase separation process of PLGA solutions in dimethylcarbonate. The parameters investigated were the PLGA concentration and the casting volume of solution. Membranes produced from 5 wt/v % polymer solutions and a 6 ml casting volume of polymer solution were selected for fabricating tubes of 3 mm diameter, 20 mm length and a nominal wall thickness of 1.5 mm. Scanning electron microscopy revealed that the structure of the tubularfoams consisted of radially oriented and highly interconnected pores with a large size distribution (50-300 µm). Selected tubes were implanted subcutaneously into adult male Lewis rats. Although the lumen of the tubes collapsed within one week of implantation, histological examination of the implanted scaffolds revealed that the foam tubes were well tolerated. Cellular infiltration into the foams, consisting mainly of fibrovascular tissue, was evident after two weeks and complete within eight weeks of implantation. The polymer was still evident in the scaffolds after eight weeks of implantation. The results from this study demonstrate that the PLGA tubular foams may be useful as soft-tissue engineering scaffolds with modification holding promise for the regeneration of tissues requiring a tubular shape scaffold such as intestine. [less ▲]

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See detailFreeze-dried poly(D,L-lactic acid) macroporous guidance scaffolds impregnated with brain-derived neurotrophic factor in the transected adult rat thoracic spinal cord
Patist, Carla M; Borgerhoff Mulder, Masha; Gautier, Sandrine et al

in Biomaterials (2004), 25(9), 1569-1582

The effects of poly(D,L-lactic acid) macroporous guidance scaffolds (foams) with or without brain-derived neurotrophic factor (BDNF) on tissue sparing, neuronal survival, axonal regeneration, and ... [more ▼]

The effects of poly(D,L-lactic acid) macroporous guidance scaffolds (foams) with or without brain-derived neurotrophic factor (BDNF) on tissue sparing, neuronal survival, axonal regeneration, and behavioral improvements of the hindlimbs following implantation in the transected adult rat thoracic spinal cord were studied. The foams were embedded in fibrin glue containing acidic-fibroblast growth factor. One group of animals received fibrin glue with acidic-fibroblast growth factor only. The foams were prepared by a thermally induced polymer-solvent phase separation process and contained longitudinally oriented macropores connected to each other by a network of micropores. Both foams and fibrin only resulted in a similar gliotic and inflammatory response in the cord-implant interfaces. With BDNF foam, up to 20% more NeuN-positive cells in the spinal nervous tissue close to the rostral but not caudal spinal cord-implant interface survived than with control foam or fibrin only at 4 and 8 weeks after implantation. Semithin plastic sections and electron microcopy revealed that cells and axons more rapidly invaded BDNF foam than control foam. Also, BDNF foam contained almost twice as many blood vessels than control foam at 8 weeks after implantation. Tissue sparing was similar in all three implantation paradigms; approximately 42% of tissue was spared in the rostral cord and approximately 37% in the caudal cord at 8 weeks post grafting. The number of myelinated and unmyelinated axons was low and not different between the two types of foams. Many more axons were found in the fibrin only graft. Serotonergic axons were not found in any of the implants and none of the axons regenerated into the caudal spinal cord. The behavioral improvements in the hindlimbs were similar in all groups. These findings indicated that foam is well tolerated within the injured spinal cord and that the addition of BDNF promotes cell survival and angiogenesis. However, the overall axonal regeneration response is low. Future research should explore the use of poly(D,L-lactic acid) foams, with or without axonal growth-promoting factors, seeded with Schwann cells to enhance the axonal regeneration and myelination response. [less ▲]

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See detailPreparation, characterization, and in vitro degradation of bioresorbable and bioactive composites based on Bioglass (R)-filled polylactide foams
Maquet, Véronique; Boccaccini, Aldo R.; Pravata, Laurent et al

in Journal of Biomedical Materials Research, Part A (2003), 66A(2), 335-346

Highly porous poly(D,L-lactide)/Bioglass composites scaffolds were prepared by thermally induced phase separation process of polymer solutions and subsequent solvent sublimation. A series of composite ... [more ▼]

Highly porous poly(D,L-lactide)/Bioglass composites scaffolds were prepared by thermally induced phase separation process of polymer solutions and subsequent solvent sublimation. A series of composite foams with different polymer/Bioglass weight ratios was prepared to study the influence of Bioglass content on the foam characteristics such as porous structure, density, and pore volume. The pore volume was decreased from 9.5 to 5.7 cm(3)/g when the Bioglass content was increased up to 40 wt %, but the overall pore morphology was not affected very much by changing the polymer/glass composition ratio. The composites foams were then incubated in phosphate-buffered saline at 37 degrees C to study the in vitro degradation of the polymer and to detect hydroxyapatite (HA) formation as an indication of their bioactivity. The addition of Bioglass to polymer foams increased the water absorption and weight loss as compared with pure polymer foams. However, the polymer molecular weight, determined by size exclusion chromatography, was found to decrease more rapidly and to a larger extent in absence of Bioglass. This delayed degradation rate in the composite foams was probably caused by the dissolution of alkaline ions from the Bioglass, resulting in a buffering effect of the incubation medium. After incubation for 7 days, HA was detected by X-ray diffractometry and Raman spectroscopy and confirmed by environmental scanning electron microscopy and energy-dispersive X-ray analysis. The porous composites developed here are promising materials for bone regeneration applications because the formation of HA on the surface of the pore walls should provide good environment for the adhesion and proliferation of osteoblasts and osteoprogenitor cells. [less ▲]

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See detailPreparation of macroporous biodegradable poly(L-lactide-co-epsilon-caprolactone) foams and characterization by mercury intrusion porosimetry, image analysis, and impedancy spectroscopy
Maquet, Véronique; Blacher, Silvia ULg; Pirard, René ULg et al

in Journal of Biomedical Materials Research (2003), 66A(2), 199-213

Two poly(L-lactide-co-epsilon-caprolactone) random copolymers containing 5 and 40 mol% of epsilon-CL, namely P(LA-co-CL5) and P(LA-co-CL40), respectively, have been made macroporous by freeze-drying ... [more ▼]

Two poly(L-lactide-co-epsilon-caprolactone) random copolymers containing 5 and 40 mol% of epsilon-CL, namely P(LA-co-CL5) and P(LA-co-CL40), respectively, have been made macroporous by freeze-drying solutions in dimethylcarbonate. Most of the freeze-dried foams, prepared by varying polymer concentration and cooling rate, exhibited two main pore populations: (1) longitudinally oriented tube-like macropores with diameters greater than or equal to100 mum, and (2) interconnected micropores (10-100 mum). Pore characteristics, including macropore density, mean diameter, and interdistance, as well as micropore density, area, and shape, were determined by image analysis of scanning electron micrographs in order to study the influence of processing and formulation parameters on foam structure and properties. The pore orientation and the 3-D texture also were studied by image analysis and impedance spectroscopy. In the case of the P(LA-co-CL5), the macropore diameter increased with the cooling rate while the micropore diameter decreased. The micropores also became more circular when the cooling rate was increased. The pore size and morphology of the P(LA-co-CL40) were quite unchanged by varying the cooling rate. All the other conditions being the same, the P(LA-co-CL5) foams were better organized than the P(LA-co-CL40) foams, and pore orientation was improved at the higher cooling rate. Pore size and morphology also can be controlled by changing the polymer concentration (Cp), as we showed by studying P(LA-co-CL5) foams prepared by freeze-drying solutions in the 1-10 w/v% Cp range. Macropore density, average diameter, and interdistance of P(LA-co-CL5) foams increased with Cp, but the micropore characteristics remained almost unchanged no matter the Cp. The reliability of the characterization methods has been discussed, with special attention to mercury intrusion porosimetry, which is used primarily for measurement of pore volume and pore size distribution. However, this technique is reported here as a destructive and unreliable method for the characterization of fragile P(LA-co-CL40) foams. This study shows that image analysis and impedance spectroscopy can give reliable information relative to the pore morphology and anisotropy of freeze-dried foams. [less ▲]

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See detailSurface modification of metallic stents by strongly adhering aliphatic polyesters
Aqil, Abdelhafid ULg; Voccia, Samuel; Labaye, David-Emmanuel et al

Poster (2003, May 16)

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See detailBioactive poly(α-hydroxyacids)/Bioglass® composites with a tailord porous structure and resorbability, for bone tissue engineering
Pravata, Laurent; Maquet, Véronique; Boccacini, A. R. et al

Poster (2003, May 16)

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