Biocompatibility enhancement of Mg-Gd-Ca alloy by laser surface modification

Surface properties play a significant role in the interaction between cells and implants. In this paper, the authors present a hybrid method including laser melting and laser surface texturing on Mg-Gd-Ca alloy to control cell behavior. Microstructure characterization was investigated by scanning electron microscopy, x-ray diffraction, and atomic force microscopy, and corrosion resistance was measured in Hank's solution using electrochemical measurement and hydrogen evolution. Results show that the combined effect of the dissolution of the β phase and the formation of the homogeneous a-Mg solid solution in the laser melted layer significantly improved the corrosion resistance of Mg-Gd-Ca alloy. In vitro cell culture shows that MC3T3-E1 cells exhibited good viability and adhesion behavior on the laser-modified surface. The MC3T3-E1 cells were elongated along the direction of texture due to the anisotropic and persistent mechanical stimulus effect. They propose that the enhanced performance accompanied by the simplicity of fabrication makes laser surface modification a promising candidate for biomedical applications in biomedical devices.