Plasma spray of biofunctional(Mg, Sr)-substituted hydroxyapatite coatings for titanium alloy implants

摘要

Plasma-sprayed hydroxyapatite (HA) coatings have been widely utilized in load-bearing titanium alloy implants. In this study, Mg, Sr co-substituted HA ((Mg,Sr)-HA) nano-scale powders have been synthesized, which are further used to prepare (Mg,Sr)-HA coatings on Ti-6A1-4V alloys in order to improve the biological functions. The average size of (Mg,Sr)-HA nano particles is ~75nm. The average bonding strength for (Mg,Sr)-HA coating and samples after heat treatment at 500℃ or 600℃ for 3h are 26.17±2.11 MPa, 36.07±4.48 MPa and 37.07 ±2.95 MPa, respectively. There is a significantly increase of bonding strength likely due to low residual stress after heated treatment.MC3T3-E1 cells show a high proliferation rate when cultured with (Mg,Sr)-HA coating extract compared to the normal culture medium, which also exhibit large extension and depositi on of extracellular matrices when adhered on the coating surfaces. Thus, these (Mg,Sr)-HA coatings show high bonding strength and improved biological functions, which offer promising future applications in the fields of orthopedics and dentistry.