Biomimetic coating of alumina scaffolds at different immersion times

The biomimetic method can be used to coat scaffolds with calcium phosphate to improve bioactivity. This method presents the advantages of low cost, reproducibility, and applicability to complex surface and porous structures. This study aimed to manufacture alumina scaffolds coated with calcium phosphate by a biomimetic method for use as a biomaterial. The scaffolds were compacted at 200 MPa with 40 wt.% ammonium bicarbonate and 60 wt.% alumina, subjected to heat treatment at 270 °C for 120 min, and sintered at 1500 °C for 120 min. The samples were biomimetically coated by immersing them in a simplified solution of calcium chloride dihydrate (CaCl2.2H2O) and sodium hydrogen phosphate dihydrate (Na2HPO4.2H2O) for 7, 14, and 21 days. The samples were characterized by Archimedes' principle for density and porosity determination, Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), X-ray diffraction (XRD), and Fourier-transform infrared (FTIR). The scaffolds showed a porosity of 55%, with homogeneous distribution, interconnection, and pore sizes. Calcium phosphate formation was observed on the scaffold surfaces after 21 days of biomimetic coating. The samples presented promising results for use as biocompatible scaffolds.