Optimization of hydroxyapatite coating on Ti-etched by hydrothermal method for biomedical material applications
DOI:
https://doi.org/10.54939/1859-1043.j.mst.114.2026.106-113Keywords:
Hydroxyapatite coating; HA coating; Hydrothermal method; DOE; Box-Wilson.Abstract
This study employed hydrothermal synthesis to fabricate hydroxyapatite (HA) coatings on surface-treated titanium substrates, combined with a second-order orthogonal regression model and statistical optimization techniques, including Response Surface Methodology (RSM) and Analysis of Variance (ANOVA), to optimize key processing parameters. The formation of a single-phase HA coating with nanoscale features on the titanium substrate was confirmed by X-ray diffraction (XRD) and FESEM-EDS analyses, together with evidence of excellent biocompatibility. The HA-coated samples were further evaluated through in vitro testing using baby hamster kidney (BHK) cells, demonstrating favorable cell proliferation and detailed cellular morphology observed by confocal laser scanning microscopy (CLSM). The RSM analysis identified the optimal processing conditions as follows: hydrothermal temperature (T1) of 216.5 °C, hydrothermal time (T2) of 40.2 h, and titanium substrate treatment time in an HCl/H₂SO₄ acid mixture at 60 °C (T3) of 65.3 minutes. Under these optimized conditions, the HA coating achieved a maximum shear strength of 7.52 MPa. This HA coating on a treated titanium substrate holds strong potential in biomedical applications, particularly in military medicine for bone implants and prosthetic replacement components.
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