Titanium surfaces coated with alginate/hydroxyapatite composites by dip-coating technique

Abstract Alginate/Hydroxyapatite (Alg/HA) composites at different ratios (Alg_pure, 5:1, 4:1, 3:1, 2:1) were deposited on titanium (Ti) surface using the dip-coating technique. The influence of composition on coating homogeneity, morphology, and physicochemical properties was systematically investigated. FITR, Raman, XRD, and SEM/EDS analyses confirmed the presence of HA phase within the polymer matrix. The Alg2:1HA coating displayed cracks in the Alg/HA interface, suggesting saturation of polymer matrix. The rheological assays displayed all suspensions exhibited non-Newtonian shear-thinning behavior. The profilometry assessments indicated that all coatings exhibited suitable micro-roughness for promoting osseointegration. SEM/FIB and optical microscopy revealed that the Alg3:1HA and Alg2:1HA coatings demonstrated good adhesion and mechanical strength when subjected to tensile stress in a three-point bending test. However, Alg3:1HA coating demonstrated a more favorable properties, with no cracks in the Alg/HA interface. Overall, these findings contribute valuable insights toward the development of bioactive, mechanically resistant coatings for orthopedic and dental applications.