Anodized AZ91D magnesium alloy: electrochemical, surface and cell culturing studio

GÓMEZ-SANCHEZ, ANDREA; MERLO, JULIETA LETICIA; KATUNAR, MARÍA ROSA; MORENO, JULIETA; CERÉ, SILVIA

Monitored from Québec due to COVID-19 pandemic

Workshop; Updates in Bioabsorbable Metals 2020; 2020

INTRODUCTION: The main limitation for the application ofMg-alloys as biomedical devices is the hydrogen evolution that results fromtheir corrosion in aqueous media. In order to decrease the release of hydrogenfrom Mg-based metals, a number of strategies have been proposed [1]. Anodizingis one alternative, but many of the protocols used included hazardous compounds(e.g. chromates or fluorides) or high current densities.  In the present study AZ91D Mg alloy was anodizedwith an environmentally-friendly low cost process, with the aim of controllinghydrogen evolution and modify the surface and hence generatinga potential material for orthopaedic devices.METHODS: Extrudedmagnesium alloy AZ91D (Al 9.0, Zn 1.0, Fe 0.005, Mn 0.33, Ni 0.002 wt %; MagIC,Magnesium Innovations Center, Germany) were polished up to 1200 grit SiC emerypaper.  Anodizing was performed at 5 V 5mol/L potassium hydroxide solution (KOH, Sigma Aldrich). Non anodized sampleswere used as control. All samples were sterilized by dry air (180° C), for 2 h.Surface was studied by Raman Spectroscopy, SEM, and roughness was assessedusing a profilometer. Electrochemical tests (polarization curves and EIS) wereconducted in simulated body fluid at 37° C. The influence of the anodizing on the cellularadhesion and viability was assessed using by primaryculture bovine embryonic fibroblasts (BEFs) and  isolated from bovine embryos were cultured inDMEM under standard cell culture. Biocompatibility of anodizing samples wasalso evaluated through the use of the pre-osteoblastic-likecell line MC3T3-E1, respectively.