Enhanced corrosion resistance and cytocompatibility of biodegradable Mg alloys by introduction of Mg(OH) particles into poly (L-lactic acid) coating.

A strategy of suppressing the fast degradation behaviour of Mg-based biomaterials by the introduction of one of Mg degradation products Mg(OH) was proposed according to the following degradation mechanism, Mg + 2HO ⇋ Mg(OH) + H↑. Specifically, Mg(OH) submicron particles were mixed into poly (L-lactic acid) (PLLA) to synthesize a composite coating onto hydrofluoric acid-pretreated Mg-Nd-Zn-Zr alloy. The in vitro degradation investigations showed that the addition of Mg(OH) particles not only slowed down the corrosion of Mg matrix, but also retarded the formation of gas pockets underneath the polymer coating.