title: Synthesis, mechanical and biological characterization of ionic doped carbonated hydroxyapatite/β-tricalcium phosphate mixtures.
abstract: The influence of ionic substituents in calcium phosphates intended for bone and tooth replacement biomedical applications is an important research topic, owing to the essential roles played by trace elements in biological processes. The present study investigates the mechanical and biological evaluation of ionic doped hydroxyapatite/β-tricalcium phosphate mixtures which have been prepared by a simple aqueous precipitation method. Heat treating the resultant calcium phosphates in a carbonated atmosphere led to the formation of ionic doped carbonated hydroxyapatite/β-tricalcium phosphate mixtures containing the essential ions of biological apatite. The structural analysis determined by Rietveld refinement confirmed the presence of hydroxyapatite as the main phase, together with a considerable amount of β-tricalcium phosphate. Such phase assemblage is essentially due to the influence of substituted ions during synthesis. The results from mechanical tests proved that carbonate substitutions are detrimental for the mechanical properties of apatite-based ceramics. In vitro proliferation assays of osteoblastic-like cells (MC3T3-E1 cell line) to powders revealed that carbonate incorporation can either delay or accelerate MC3T3 proliferation, although reaching the same proliferation levels as control cells after 2 weeks in culture. Further, the powders enable pre-osteoblastic differentiation in a similar manner to control cells, as indirectly measured by ALP activity and Type-I collagen medium secretion.
authors.affiliation: Department of Ceramics and Glass Engineering, University of Aveiro, CICECO, Aveiro, Portugal.
authors.forename: S
authors.initials: S
authors.lastname: Kannan
authors.forename: S I
authors.initials: SI
authors.lastname: Vieira
authors.forename: S M
authors.initials: SM
authors.lastname: Olhero
authors.forename: P M C
authors.initials: PM
authors.lastname: Torres
authors.forename: S
authors.initials: S
authors.lastname: Pina
authors.forename: O A B
authors.initials: OA
authors.lastname: da Cruz e Silva
authors.forename: J M F
authors.initials: JM
authors.lastname: Ferreira
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D002130:Calcium Phosphates / Q000138:chemical synthesis* / Q000494:pharmacology*; D002254:Carbonates / Q000737:chemistry*; D002470:Cell Survival / Q000187:drug effects; D024042:Collagen Type I / Q000378:metabolism; D017077:Culture Media, Conditioned / Q000494:pharmacology; D017886:Durapatite / Q000138:chemical synthesis* / Q000494:pharmacology*; D006244:Hardness / Q000187:drug effects; D006358:Hot Temperature; D006801:Humans; D015151:Immunoblotting; D007477:Ions; D055595:Mechanical Phenomena / Q000187:drug effects*; D051379:Mice; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects / Q000201:enzymology; D044367:Phase Transition / Q000187:drug effects; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D002130:Calcium Phosphates; D002254:Carbonates; D024042:Collagen Type I; D017077:Culture Media, Conditioned; D007477:Ions; C485817:beta-tricalcium phosphate; D017886:Durapatite; D000469:Alkaline Phosphatase