Structural, mechanical, and biocompatibility investigations of yttrium and fluoride doped nano hydroxyapatite

Burçin, Başar
In this study, it was aimed to investigate the structural, mechanical and biological properties of nano hydroxyapatite (HA) doped with yttrium and fluoride with different compositions. HAs were synthesized by precipitation method. After sintering at 900oC, 1100oC or 1300oC for 1 hour, the structural properties of HAs were investigated by XRD, FTIR spectroscopy and SEM. High relative densities (above 88 % of relative density) were achieved after sintering. No second phases were observed in XRD measurements. Hexagonal lattice parameters and unit cell volumes of doped HAs decreased indicating the substitutions of ions. Characteristics absorbtion bands of HA and additional bands due to fluoride substitutions were observed in FTIR patterns. SEM images showed that grain sizes decreased with increasing doping amounts and decreasing sintering temperatures. Discs prepared by cold pressing were sintered at 900oC, 1100oC and 1300oC for 1 hour to determine mechanical properties. Mechanical properties of HAs were found to be directly related to the sintering temperatures and amount of dopings. Biocompatibility of pure and doped HA discs was assessed with in vitro cytotoxicity studies. Cell attachment, proliferation and differentiation state of cells were studied using MTT, ALP and calcium assays and SEM. Cell attachment and proliferation were enhanced with dopings and increasing sintering temperatures. The highest ALP production and calcium deposition were observed on HAs sintered at 1100oC. In vitro studies revealed that 1100oC was the sintering temperature for best cell responses. Specifically, 2.5YFHA seemed to be promising as an alternative for pure HA among all doped HAs.


Structural, mechanical and biological properties of hydroxyapatite-zirconia-lanthanum oxide composites
Khoshsima, Sina; Yilmaz, Bengi; Tezcaner, Ayşen; Evis, Zafer (2016-11-01)
Novel hydroxyapatite-zirconia-lanthanum oxide composites for bioceramic applications were synthesized and their structural, mechanical and biological properties were studied. Pure HA was produced via precipitation method and the composites were obtained by several fabrication steps: powder milling, mixing, cold pressing and sintering at 1100 degrees C for 1 h. The experimental results indicated that the composites consisted of hydroxyapatite as the main phase with a trace amount of tricalcium phosphate. Cal...
Structural and mechanical characteristics of hydroxyapatite and tri-calcium phosphates doped with Al3+ and F- ions
Tahmasebifar, A.; Evis, Zafer (2013-08-01)
In this study, doping of aluminum (Al3+) and/or fluoride (F-) ions into tri-calcium phosphate (TCP)-hydroxyapatite (HA) composites at various compositions were performed to investigate their microstructure and mechanical properties. Composites were synthesized by a precipitation method and sintered at 1100 degrees C for 1 hr and 5 hrs. Densities of the sintered materials were increased by extending the sintering time and increasing the amount of Al3+ and F- doping. beta-TCP was observed as the main phase in...
Microstructural, biological and mechanical investigations of hydroxyapatite-β-tricalcium phosphate composites doped with strontium and fluoride
Pourreza, Elmira; Evis, Zafer; Department of Engineering Sciences (2016)
The aim of this study was to investigate the microstructure, mechanical and biological properties of biphasic hydroxyapatite--Tricalcium phosphate (HT) and HT substituted with constant fluoride (F−) and varying strontium (Sr2+) amounts. All the samples were synthesized via precipitation method and sintered at 1100°C for 1 h. It was observed that the relative density of the sintered strontium and fluoride doped HT slightly increased. For microstructural analysis, X-ray diffraction (XRD), scanning electron m...
Synthesis of silver nanoparticles by oleylamine-oleic acid reduction and its use in making nanocable by coaxial electrospinning
Çınar, Simge; MAVİŞ, BORA; Çolak, Üner (American Scientific Publishers, 2011-12-01)
In the present study, silver nanoparticles were produced by hydrazine hydrate and oleylamine/oleic acid systems in order to investigate the effects of reducing agents with different strengths on the reduction mechanism. Particle size and size distribution of silver particles produced by slow reducing system were studied in detail by using transmission electron microscopy (TEM), X-Ray Diffraction (XRD), photon correlation spectroscopy (PCS), and surface plasmon resonance spectroscopy (SPR). Finally, reductio...
Structural and mechanical investigations of magnesium and fluoride doped nanosize calcium phosphates
Evis, Zafer (2010-12-01)
Pure and Mg2+ and F doped nano-calcium phosphates (CaP), which were synthesized by a precipitation method to investigate their microstructural and mechanical properties. After the drying and calcination processes, the samples were sintered at 1100 degrees C for 1 hour. High densities were achieved except for the 7.5% mole Mg doped samples. Due to the Mg2+ substitution, beta-TCP phase was detected besides HAp, resulting in the formation of HAp/ beta-TCP biphasic composites with different compositions. The su...
Citation Formats
B. Burçin, “Structural, mechanical, and biocompatibility investigations of yttrium and fluoride doped nano hydroxyapatite,” M.S. - Master of Science, Middle East Technical University, 2009.