Synthesis and Characterization of Hydroxyapatite/Bioactive Glass Nanocomposite Foam and Fluorapatite/Bioactive Glass Nanocomposite Foam by Gel Casting Method as Cell Scaffold for Bone Tissue

Abstract

The aim of this study was to synthesize and characterization of
hydroxyapatite/bioactive glass (HA/BG) nanocomposite foam and
fluorapatite/bioactive glass (FA/BG) nanocomposite foam by gel casting method as cell
scaffold for bone tissue engineering and evaluating their bioactivity using in vitro
methods. Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD), Scanning Electron
Microscopy (SEM), Transmission Electron Microscopy (TEM), Archimedes method and
universal testing machine were used in order to evaluate specific surface area, phase
composition, shape, size and interconnectivity of pores, size and shape of the
constructed foam particles, porosity measurement and compressive strength of
prepared nanocomposite foams, respectively. Mean particle size of HA/BG and FA/BG
nanocomposite foams were 78 and 42 nm respectively with average pore size ranges
was from 100 to 400 µm for two compositions. The maximum values of compressive
strength and elastic modulus of nanocomposite foams were 0.22 and 17.8 Mpa for
HA/BG and 0.13 and 22 MPa for FA/BG, respectively. The mean values of the apparent
and true porosity were calculated 31 and 78% for HA/BG and 42 and 77% for FA/BG,
respectively. The results of in vitro immersion of foams in simulated body fluid (SBF)
demonstrate the formation of apatite on the surface of foams that indicating their
bioactivity. The prepared nanocomposite foams in this research are appropriate
substitutes for the bone defects in tissue engineering due to their characteristics.
Moreover, using gel casting method to introduce these bioceramics provides the
possibility to construct foams by molding or 3D printing in a desired shapes in
accordance to patient’s needs with high dimensional accuracy