Porous foams based hydroxyapatite prepared by direct foaming method using egg white as a pore promoter

Abstract

Stoichiometric Hydroxyapatite (Ca10(PO)6(OH)2, HAP) foams, have been produced. The porous parts were prepared from a calcined HAP powder and egg white as a bio and nontoxic pore promoter. The colloidal slurry was prepared, poured into cylindrical molds, dried, unmolded, and sintered at 1200 °C. The effects of the concentration of the solid loading, of the dispersing agent, and the foaming agent on the ceramic preparation were examined. X-Ray Diffraction (XRD) and Fourier Transform Infrared (FTIR) were used to evaluate the composition and the structure of the sintered HAP ceramics. Scanning Electron Microscopy (SEM) was used for microstructural analysis. The XRD analysis of the porous parts, prepared under optimized conditions, showed the presence of crystalized HAP (JCPDS 9-432) as a single phase. SEM images showed existence of open and interconnected micro and macro-pores in the ceramics. The use of the egg white protein as pore former provides a total porosity of 86 vol-% and a foam-structure that allows to a micro-porous wall.

Characterization of β-tricalcium phosphate-clay mineral composite obtained by sintering powder of apatitic calcium phosphate and montmorillonite

“…On the other hand, numerous works of literature reported that the use of montmorillonite improve the mechanical properties of the calcium phosphate blocks and foams [31,48]. Also, we have reported in previous work [49] that the hydroxyapatite parts made with montmorillonite showed an appropriate mechanical stability of the sintered parts compared to those prepared without montmorillonite. The addition of clay generally promotes the densification of materials.…”

Ceramic hydroxyapatite foam as a new material for Bisphenol A removal from contaminated water

“…The band detected at around 3500 cm -1 was attributed to the water adsorbed on the surface of the HAP foam. The pores were formed due to space created by air bubbles and also by the burning-out of the egg-protein as it was already discussed in our previous work (Khallok et al 2019). The obtained CF-HAP has a wide variation in porosity and pore size from 1 to 650 µm (Fig.…”

“…The HAP foam (CF-HAP) was prepared by a combination of the direct foaming and the slip-casting techniques using an aqueous suspension of the sintered HAP powder and egg white as a pore promoter following the procedure described in our previous work (Khallok et al 2019). The obtained foam was poured into a silicone cylindrical mold (3 cm in diameter and 0.5 cm in high) and dried first at 80°C for one hour and then at 105°C for 24 h. The dried CF-HAP was calcined first at 600°C and then at 1200°C for further consolidation of the structure.…”

Formation of Porous Apatite Layer after Immersion in SBF of Fluorine-Hydroxyapatite Coatings by Pulsed Laser Deposition Improved in Vitro Cell Proliferation

“…The surface of HA coatings with and without annealing treatment was covered with the newly formed apatite layer, which did not lead to a significant change in the morphology. It was confirmed that it was difficult to construct porous structures on HA coatings . In contrast, F-HA coatings without annealing treatment exhibited a loose spongy structure, forming a spherical apatite layer with a diameter of 3–5 μm (Figure c 1 ).…”

“…The porosities of F-HA coatings (Figure c,d) were 52.6 and 72.8%. For a new bone growth, the interconnected nanopores, particularly the meso/nanopores, can effectively ensure the absorption of the necessary nutrients for the bone growth. , …”