Durability of AZ31 magnesium biodegradable alloys polydopamine aided: Part 1

The use of magnesium alloys, as a biodegradable medical device, is an interesting challenge for the biomaterials field. Its rapid degradation and the release of hydrogen, when exposed to biological fluids, are the main drawbacks for clinical applications. In this work, a coating made of polydopamine (PDOPA), is used as an intermediate layer to decrease the degradation rate of AZ31 magnesium alloy/polymeric coating system, when exposed to Hank's solution. Experimental results highlighted: (i) the formation of a thin PDOPA layer, (ii) an increased adhesion in the organic coating/metallic substrate system, (iii) a decrease of two orders of magnitude of the corrosion rate when the PDOPA film is used together with an external organic coating, (iv) the efficacy in the use of PDODA due to the synergistic effect of both, physical and chemical, interactions between the PDOPA layer and the organic coating.