The preparation, cytocompatibility, and in vitro biodegradation study of pure beta-TCP on magnesium

Biodegradable and bioactive beta-tricalcium phosphate (beta-TCP) coatings were prepared on magnesium (Mg) in order to improve its biocompatibility by a chemical method. The tensile bonding strength of beta-TCP coating and Mg substrate was measured by the standard adhesion test (ISO 13779-4). And the cytocompatibility of beta-TCP coated Mg was studied by using human osteoblast-like MG63 cells. It was found that the MG63 cells could grow well on the surface of beta-TCP coated Mg and the cell viability on beta-TCP coated Mg was above 80% during the cocultivation of MG63 cells and beta-TCP coated Mg for 10 days, indicating no cytotoxicity. It was concluded that the beta-TCP coated Mg had good cytocompatibility. The degradation of Mg substrate with beta-TCP coating in vitro was studied in detail by XRD, EDX, SEM, and ICP. The results showed that a bone-like apatite continually formed on the surface of the sample with the degradation of both Mg substrate and beta-TCP coating in Hank's solution (a simulated body fluid). The biodegradation mechanism was preliminarily analyzed in the paper.