Self-healing dicalcium phosphate dihydrate coating of biomedical magnesium and its in vitro biocompatibility evaluation

Abstract

To improve the corrosion resistance and biocompatibility of magnesium (Mg) for biomedical applications, a novel coating comprising self-healing dicalcium phosphate dihydrate (DCPD) was applied to Mg using a simple deposition method, without the need for the addition of corrosion inhibitors. Scratch and immersion tests demonstrated that the prepared coating displayed impressive self-healing capabilities, with artificial scratches within 4 h when exposed to 0.9 wt% NaCl solution. The electrochemical test suggested that the DCPD-coating, whether scratched or not, provided effective corrosion protection for the Mg substrate. In vitro cell culture results revealed that the DCPD-coated samples exhibited superior biocompatibility compared to pure Mg. This work offers a new perspective on designing self-healing coatings for Mg, eliminating the need for additional corrosion inhibitors.