title: The role of hydroxyapatite as solid signal on performance of PCL porous scaffolds for bone tissue regeneration.
abstract: Highly porous composites made up of biodegradable poly-epsilon-caprolactone (PCL) and stoichiometric hydroxyapatite (HA) particles have been developed as substrate for bone-tissue regeneration. The processing technique consists of phase inversion and particulate (salt crystals) leaching. Three different HA contents (13, 20 and 26 vol %) in PCL-based composite were considered in this study. Pore microstructure with fully interconnected network and pore sizes ranging around a few hundred of mum (macroporosity) was obtained as a result of salt particles removal by leaching process. Several microns (microporosity) porosity was also created through phase inversion of polymer solution. Total porosity up to 95% was achieved. Human marrow stromal cells (MSC) were seeded onto porous PCL-based composites for 1-5 weeks and cultured in osteogenic medium. MSC were able to adhere and grow on PCL-based substrates with a plateau at 3-4 weeks. However, the small effect of bioactive signals on the biological response evaluated in MSC cell culture suggests a prior role of topography on the biological response. Importantly, the presence of HA as a bioactive solid signal determines an increase of mechanical properties. On the overall, the results indicated that porous PCL-based composites are potential candidate for bone substitution with beneficial influence on structural characteristics by solid signal addition.
authors.affiliation: Institute of Composite and Biomedical Materials, National Research Council and CRIB, University of Naples "Federico II" Piazzale Tecchio 80, 80125 Naples, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Guarino
authors.forename: Filippo
authors.initials: F
authors.lastname: Causa
authors.forename: Paolo A
authors.initials: PA
authors.lastname: Netti
authors.forename: Gabriela
authors.initials: G
authors.lastname: Ciapetti
authors.forename: Stefania
authors.initials: S
authors.lastname: Pagani
authors.forename: Desiree
authors.initials: D
authors.lastname: Martini
authors.forename: Nicola
authors.initials: N
authors.lastname: Baldini
authors.forename: Luigi
authors.initials: L
authors.lastname: Ambrosio
mesh_terms: D001854:Bone Marrow Cells; D001861:Bone Regeneration; D001842:Bone and Bones / Q000166:cytology*; D018929:Cell Culture Techniques; D017886:Durapatite / Q000737:chemistry*; D006801:Humans; D019563:Mechanics; D011091:Polyesters / Q000737:chemistry*; D016062:Porosity; D017154:Stromal Cells / Q000166:cytology; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D011091:Polyesters; C016240:polycaprolactone; D017886:Durapatite