title: New porous polycaprolactone-silica composites for bone regeneration.
abstract: Polycaprolactone porous membranes were obtained by freeze extraction of dioxane from polycaprolactone-dioxane solid solutions. Porosities as high as 90% with interconnected structures were obtained by this technique. A silica phase was synthesized inside the pores of the polymer membrane by sol-gel reaction using tetraethylorthosilicate (TEOS) as a silica precursor and catalyzed in acidic and basic conditions. Two different morphologies of the inorganic phase were obtained depending on the type of catalyst. In acid catalyzed sol-gel reaction, a homogeneous layer of silica was deposited on the pores, and discrete microspheres were synthesized on the pore walls when a basic catalyst was used. The morphology of the inorganic phase influenced the mechanical and thermal behavior, as well as the hydrophilic character of the composites. Bioactivity of the porous materials was tested in vitro by measuring the deposition of hydroxyapatite on the surfaces of the porous composite membranes. Polycaprolactone/silica composites revealed a superior bioactivity performance compared with that of the pure polymer; evidenced by the characteristic cauliflower structures on the material surface, increase in weight and Ca/P ratio of the hydroxyapatite layer. Also, the acid catalyzed composites presented better bioactivity than the base catalyzed composites, evidencing the importance in the morphology of the silica phase.
authors.affiliation: Universidad Nacional de Colombia, Sede Bogotá, Facultad de Ciencias, Departamento de Farmacia, Grupo de Procesos Químicos y Bioquímicos, Av. Cra 30 45-03, Bogotá, Código Postal 111321 Colombia; Center for Biomaterials and Tissue Engineering, Universitat Politècnica de València, Camino de Vera s/n, E-46022 Valencia, Spain.
authors.forename: Clara E
authors.initials: CE
authors.lastname: Plazas Bonilla
authors.affiliation: Center for Biomaterials and Tissue Engineering, Universitat Politècnica de València, Camino de Vera s/n, E-46022 Valencia, Spain.
authors.forename: Sara
authors.initials: S
authors.lastname: Trujillo
authors.affiliation: Ankara University Stem Cell Institute, TEBN Laboratory, Ankara, Turkey; Ankara University Faculty of Science, TEBN Laboratory, Ankara, Turkey.
authors.forename: Bermali
authors.initials: B
authors.lastname: Demirdögen
authors.affiliation: Universidad Nacional de Colombia, Sede Bogotá, Facultad de Ingeniería, Departamento de Ingeniería Química y Ambiental, Grupo de Procesos Químicos y Bioquímicos, Av. Cra 30 45-03, Bogotá, Código Postal 111321 Colombia.
authors.forename: Jairo E
authors.initials: JE
authors.lastname: Perilla
authors.affiliation: Ankara University Stem Cell Institute, TEBN Laboratory, Ankara, Turkey; Ankara University Faculty of Science, TEBN Laboratory, Ankara, Turkey.
authors.forename: Y
authors.initials: Y
authors.lastname: Murat Elcin
authors.affiliation: Center for Biomaterials and Tissue Engineering, Universitat Politècnica de València, Camino de Vera s/n, E-46022 Valencia, Spain; CIBER en Bioingeniería Biomateriales y Nanomedicina (CIBER-BBN), Valencia, Spain. Electronic address: jlgomez@ter.upv.es.
authors.forename: José L
authors.initials: JL
authors.lastname: Gómez Ribelles
mesh_terms: D001861:Bone Regeneration / Q000502:physiology*; D017886:Durapatite / Q000737:chemistry; D005782:Gels / Q000737:chemistry; D011091:Polyesters / Q000737:chemistry*; D016062:Porosity; D012821:Silanes / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry*; D013696:Temperature; D014867:Water / Q000737:chemistry
chemical_list: D005782:Gels; D011091:Polyesters; D012821:Silanes; D014867:Water; C016240:polycaprolactone; C040733:tetraethoxysilane; D012822:Silicon Dioxide; D017886:Durapatite
keywords: Bioactivity; Bone regeneration; Polycaprolactone–silica composite; Porous polymer composites; Sol–gel reaction