Preparation of high strength macroporous hydroxyapatite scaffold

Area of Science:

• Biomaterials Science
• Materials Engineering
• Ceramic Science

Background:

• Hydroxyapatite (HAp) is a key biomaterial for bone regeneration.
• Developing macroporous HAp scaffolds with tailored mechanical properties and bioactivity is crucial for orthopedic applications.

Purpose of the Study:

• To fabricate and characterize high-strength macroporous HAp scaffolds using naphthalene and benzene.
• To investigate the effect of benzene incorporation on the mechanical properties, porosity, and pore size distribution of HAp scaffolds.
• To evaluate the in-vitro bioactivity of the fabricated scaffolds.

Main Methods:

• Wet-chemical synthesis of phase-stable HAp powder up to 1250 °C.
• Fabrication of macroporous HAp-naphthalene (HN) and HAp-naphthalene-benzene (HNB) scaffolds via sintering.
• Characterization using X-ray Diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and mercury porosimetry.
• In-vitro bioactivity assessment in Simulated Body Fluid (SBF).

Main Results:

• HAp scaffolds exhibited ~60 vol.% porosity, ~11 MPa compressive strength, and ~125 μm average pore diameter.
• Benzene incorporation in HN scaffolds reduced strength but enhanced porosity and pore size distribution.
• XRD, FTIR, SEM, and porosimetry confirmed phase purity, morphology, and pore characteristics.
• In-vitro studies demonstrated nucleation of carbonated apatite on HN and HNB scaffold surfaces in SBF.

Conclusions:

• Macroporous HAp scaffolds with tunable properties can be fabricated using sintering.
• Benzene incorporation offers a method to enhance porosity and pore size in HAp scaffolds.
• The fabricated HN and HNB scaffolds exhibit good in-vitro bioactivity, indicating potential for bone tissue engineering.