title: A biocompatible hybrid material with simultaneous calcium and strontium release capability for bone tissue repair.
abstract: The increasing interest in the effect of strontium in bone tissue repair has promoted the development of bioactive materials with strontium release capability. According to literature, hybrid materials based on the system PDMS-SiO2 have been considered a plausible alternative as they present a mechanical behavior similar to the one of the human bone. The main purpose of this study was to obtain a biocompatible hybrid material with simultaneous calcium and strontium release capability. A hybrid material, in the system PDMS-SiO2-CaO-SrO, was prepared with the incorporation of 0.05 mol of titanium per mol of SiO2. Calcium and strontium were added using the respective acetates as sources, following a sol-gel technique previously developed by the present authors. The obtained samples were characterized by FT-IR, solid-state NMR, and SAXS, and surface roughness was analyzed by 3D optical profilometry. In vitro studies were performed by immersion of the samples in Kokubo's SBF for different periods of time, in order to determine the bioactive potential of these hybrids. Surfaces of the immersed samples were observed by SEM, EDS and PIXE, showing the formation of calcium phosphate precipitates. Supernatants were analyzed by ICP, revealing the capability of the material to simultaneously fix phosphorus ions and to release calcium and strontium, in a concentration range within the values reported as suitable for the induction of the bone tissue repair. The material demonstrated to be cytocompatible when tested with MG63 osteoblastic cells, exhibiting an inductive effect on cell proliferation and alkaline phosphatase activity.
authors.affiliation: CICECO - Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: J Carlos
authors.initials: JC
authors.lastname: Almeida
authors.affiliation: Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar Tudósok körútja 2, Budapest 1117, Hungary.
authors.forename: András
authors.initials: A
authors.lastname: Wacha
authors.affiliation: Laboratory for Bone Metabolism and Regeneration, Faculdade de Medicina Dentária, Universidade do Porto, Portugal.
authors.forename: Pedro S
authors.initials: PS
authors.lastname: Gomes
authors.affiliation: C2TN, Instituto Superior Técnico, Universidade de Lisboa, E.N.10, 2695-066 Bobadela LRS, Portugal.
authors.forename: Luís C
authors.initials: LC
authors.lastname: Alves
authors.affiliation: CICECO - Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: M Helena Vaz
authors.initials: MH
authors.lastname: Fernandes
authors.affiliation: CICECO - Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal. Electronic address: isabelmsalvado@ua.pt.
authors.forename: Isabel M Miranda
authors.initials: IM
authors.lastname: Salvado
authors.affiliation: Laboratory for Bone Metabolism and Regeneration, Faculdade de Medicina Dentária, Universidade do Porto, Portugal.
authors.forename: M Helena R
authors.initials: MH
authors.lastname: Fernandes
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology; D018786:Bone Substitutes / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology; D002118:Calcium / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D003692:Delayed-Action Preparations / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology; D004129:Dimethylpolysiloxanes / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology; D006801:Humans; D010006:Osteoblasts / Q000378:metabolism*; D013324:Strontium / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology
chemical_list: D001672:Biocompatible Materials; D018786:Bone Substitutes; D003692:Delayed-Action Preparations; D004129:Dimethylpolysiloxanes; C013830:baysilon; D002118:Calcium; D013324:Strontium
keywords: Biocompatible; Hybrid materials; Strontium