Microstructure, Corrosion Resistance and Biocompatibility of Biomimetic HA-Based Ca-P Coatings on ZK60 Magnesium Alloy

摘要

Recently, magnesium alloys have attracted much attention as a metallic biodegradable implant becauseof their excellent biocompatibility and mechanical compatibility. However, magnesium has a poorcorrosion resistance due to its active chemical properties, which limited the application in orthopedicsurgery. In this work, Ca-deficit hydroxyapatite (HAp) coatings were prepared on the ZK60magnesium alloys by a biomimetic method. The revised SBF solutions with pH value of 5~7 and Ca/Pratio of 1.67 were used. The coatings were composed of ball-like CaP particles with the Ca/P ratio of0.86~1.24. Electrochemical corrosion, in vitro immersion and cytotoxic tests were conducted toevaluate the corrosion resistance and biocompatibility. The corrosion resistance and biocompatibilityof the coated samples were greatly improved comparing with that of the uncoated sample. For thesamples fabricated at different pH values, the sample coated from the solution with pH of 6 has thebest corrosion resistance and biocompatibility.