Documents disponibles écrits par cet auteur

Nanostructured PLLA-hydroxyapatite scaffolds produced by a supercritical assisted technique / Ernesto Reverchon in Industrial & engineering chemistry research, Vol. 48 N° 11 (Juin 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 11 (Juin 2009) . - pp. 5310–5316 Titre : Nanostructured PLLA-hydroxyapatite scaffolds produced by a supercritical assisted technique Type de document : texte imprimé Auteurs : Ernesto Reverchon, Auteur ; Paola Pisanti, Auteur ; Stefano Cardea, Auteur Année de publication : 2009 Article en page(s) : pp. 5310–5316 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Bone  scaffolds  Nanostructural  properties  Supercritical  fluid  assisted  technique  Hydroxyapatite  nanoparticles Résumé : Temporary bone scaffolds can surrogate the extracellular matrix to favor the regeneration of tissues and organs. It is very difficult to obtain the coexistence of the macro-, micro-, and nanostructural properties necessary to mimic the organization of the human bone. To obtain all of these characteristics, we tested a supercritical fluid assisted technique for the formation of PLLA/ceramic scaffolds using hydroxyapatite (HA) nanoparticles loaded at up to 50% by weight of the polymer to improve the biomimethism and the mechanical properties of the scaffolds. We produced poly(l-lactic acid) scaffolds in relatively short time (<30 h), with a porosity higher than 90% and with a high interconnectivity. An internal structure formed by very long nanofibers of 200−400 nm diameter and prefixed macroscopic shape and size was also obtained. A maximum compressive modulus of 123 kPa was obtained, and the solvent residue was lower than 5 ppm. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8018752 [article] Nanostructured PLLA-hydroxyapatite scaffolds produced by a supercritical assisted technique [texte imprimé] / Ernesto Reverchon, Auteur ; Paola Pisanti, Auteur ; Stefano Cardea, Auteur . - 2009 . - pp. 5310–5316. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 11 (Juin 2009) . - pp. 5310–5316 Mots-clés : Bone  scaffolds  Nanostructural  properties  Supercritical  fluid  assisted  technique  Hydroxyapatite  nanoparticles Résumé : Temporary bone scaffolds can surrogate the extracellular matrix to favor the regeneration of tissues and organs. It is very difficult to obtain the coexistence of the macro-, micro-, and nanostructural properties necessary to mimic the organization of the human bone. To obtain all of these characteristics, we tested a supercritical fluid assisted technique for the formation of PLLA/ceramic scaffolds using hydroxyapatite (HA) nanoparticles loaded at up to 50% by weight of the polymer to improve the biomimethism and the mechanical properties of the scaffolds. We produced poly(l-lactic acid) scaffolds in relatively short time (<30 h), with a porosity higher than 90% and with a high interconnectivity. An internal structure formed by very long nanofibers of 200−400 nm diameter and prefixed macroscopic shape and size was also obtained. A maximum compressive modulus of 123 kPa was obtained, and the solvent residue was lower than 5 ppm. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8018752

Supercritical phase Inversion to form drug-loaded poly(vinylidene fluoride-co-hexafluoropropylene) membranes / Stefano Cardea in Industrial & engineering chemistry research, Vol. 49 N° 6 (Mars 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2783–2789 Titre : Supercritical phase Inversion to form drug-loaded poly(vinylidene fluoride-co-hexafluoropropylene) membranes Type de document : texte imprimé Auteurs : Stefano Cardea, Auteur ; Margherita Sessa, Auteur ; Ernesto Reverchon, Auteur Année de publication : 2010 Article en page(s) : pp. 2783–2789 Note générale : Inustrial Chemistry Langues : Anglais (eng) Mots-clés : Drug;  Poly;  vinylidene;  fluoride;  co-hexafluoropropylene;  Membranes Résumé : Membranes loaded with an active principle are one of the alternatives proposed to obtain controlled release pharmaceutical formulations. Until now, several methods have been proposed for the fabrication of membranes as drug delivery devices, such as phase inversion, gas foaming/particulate leaching, and solvent evaporation. Supercritical CO2 (SC-CO2) phase inversion offers an alternative process to obtain solvent-free membranes with short processing times, avoiding the collapse of the structure. We prepared poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF−HFP) loaded membranes by SC-CO2 phase inversion, performing experiments at pressures ranging between 150 and 250 bar and at temperatures ranging between 35 and 55 °C. We selected as the base case the PVDF−HFP−acetone solution at 15% w/w polymer and modified the drug (amoxicillin) concentration from 20 to 50% w/w with respect to PVDF−HFP. Different membranes morphologies, ranging from nanometric gel-like networks (mean pores diameter of about 150 nm) to micrometric cellular structures (mean cells diameter ranging between 5 and 12 μm), and different drug distributions were obtained, depending on the process conditions. Drug-controlled release experiments were also performed to study the kinetics and duration of the release process. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901616n [article] Supercritical phase Inversion to form drug-loaded poly(vinylidene fluoride-co-hexafluoropropylene) membranes [texte imprimé] / Stefano Cardea, Auteur ; Margherita Sessa, Auteur ; Ernesto Reverchon, Auteur . - 2010 . - pp. 2783–2789. Inustrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2783–2789 Mots-clés : Drug;  Poly;  vinylidene;  fluoride;  co-hexafluoropropylene;  Membranes Résumé : Membranes loaded with an active principle are one of the alternatives proposed to obtain controlled release pharmaceutical formulations. Until now, several methods have been proposed for the fabrication of membranes as drug delivery devices, such as phase inversion, gas foaming/particulate leaching, and solvent evaporation. Supercritical CO2 (SC-CO2) phase inversion offers an alternative process to obtain solvent-free membranes with short processing times, avoiding the collapse of the structure. We prepared poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF−HFP) loaded membranes by SC-CO2 phase inversion, performing experiments at pressures ranging between 150 and 250 bar and at temperatures ranging between 35 and 55 °C. We selected as the base case the PVDF−HFP−acetone solution at 15% w/w polymer and modified the drug (amoxicillin) concentration from 20 to 50% w/w with respect to PVDF−HFP. Different membranes morphologies, ranging from nanometric gel-like networks (mean pores diameter of about 150 nm) to micrometric cellular structures (mean cells diameter ranging between 5 and 12 μm), and different drug distributions were obtained, depending on the process conditions. Drug-controlled release experiments were also performed to study the kinetics and duration of the release process. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901616n