Microstructure, microhardness, and biocompatibility characteristics of yttrium hydroxyapatite doped with fluoride

Abstract

The current study focused on doping of hydroxyapatite (HA) with constant yttrium (Y(3+) ) and varying fluoride (F(-) ) compositions to investigate its microstructure, microhardness, and biocompatibility. HA was synthesized by precipitation method and sintered at 1100°C for 1 h. Y(3+) and F(-) ion dopings resulted in changes in densities. In x-ray diffraction analysis, no secondary phase formation was observed. Lattice parameters decreased upon ion substitutions. Scanning electron microscopy (SEM) results showed that ion addition resulted in smaller grains. In Fourier transform infrared spectroscopy analysis, F(-) ion substitution was confirmed. HA doped with 2.5% Y(3+) and 1% F(-) exhibited the highest microhardness. Y(3+) and F(-) ions improved Saos-2 cell proliferation on discs in Methylthiazolyldiphenyl-tetrazolium (MTT) assay. In SEM analysis, cells attached and proliferated on all disc surfaces. Alkaline phosphatase (ALP) assay showed that cell differentiation on the discs was improved by doping HA with an optimum F(-) amount. Dissolution tests revealed that structural stability of HA was improved with F(-) ion incorporation. The dissolution behavior of fluoridated samples exhibited a parallel pattern with the cell proliferation and differentiation behavior on these samples. Overall, this work shows that fluoride and yttrium cosubstitution into HA HA2.5Y1F was the most promising material for biomedical applications.

Cationic and Anionic Substitutions in Hydroxyapatite

“…Moreover, Y 3+ ions had showed to be able to promote Saos-2 cell proliferation by methylthiazolyldiphenyl-tetrazolium (MTT) assay [276]. Accordingly, Webster et al concluded that Y induces a greater osteoblast adhesion on bulk HAp doped with Y (up to 7 mol%) with respect to pure HAp [72].…”

Structural insights of mechanically induced aluminum-doped hydroxyapatite nanoparticles by Rietveld refinement

“…These structural modifications can alter the solubility, thermal stability, and mechanical properties as well as the in-vitro bioactivity of HA crystals [16][17][18][19]. Over the past decades, many different methods have been introduced for the production of various substituted apatites with precise control of the microstructure, particle shape and size [20][21][22][23][24].…”

Silver release of Ag (I) doped hydroxyapatite: In vitro study

“…However, little is known about the effects of the new molecular structure formed as a result of the doping (Khan et al, ). The replacement of ions in the nHAp structure with different ions in application area may alter the solubility, thermal stability and mechanical properties of nHAp crystals (Nasiri‐Tabrizi & Fahami, ; Toker et al, ). Therefore, it is important to mimic the body environment in the release study.…”