Effect Of CaP-particles on Ceramic-like Coatings Formed on Magnesium via Anodisation

Successful bone regeneration is a complex physiological process that leads to the formation of new functional bone tissue. Bone formation around the orthopedic implants is in a special focus due to numerous complications in the postoperative period. Biodegradable implants (particularly Mg-based prosthesis) open new perspectives in regenerative medicine but suffer from fast uncontrolled degradation [1]. Plasma Electrolytic Oxidation technology could be an ideal choice for degradable implant modification with enhanced wear and corrosion resistance, improved biocompatibility, and biodegradability [2]. Recent designs of anodizing procedure are focused on using CaP-particles suspensions, aiming at in-situ incorporation or sealing the porous coatings and endowing the layers with new functionalities [3]. In our investigation, we used the strategy of particle incorporation into the coating with no formation of a new phase. Preservation of the particle's primary chemical composition, shape, and size allows to produce high biocompatible surface with enhanced wear resistance. The magnesium samples were treated in a silicate-based solution with the addition of the crystalline commercial spray-dried stoichiometric hydroxyapatite (Ca10(PO4)6(OH)2) powder and amorphous tricalcium phosphate (Ca3(P04)2) powder. Scanning electron microscopy images revealed particles' incorporation into the coating with location on the surface and inside the pores of ceramic layer. The hydroxyapatite addition to the solution resulted in increasing roughness and wettability of the surface. Preliminary investigation demonstrated the potential application of new hydroxyapatite ceramic coating for medical application.