Study On Biocompatibility Of Mg-based Amorphous Film

When the fraction of Zn of Mg-Zn-Cametallic glass(MG)reaches a certain threshold(?28 at.%),it can significantly reduce the evolution of hydrogen and effectively avoid the occurrence of hydrogen balloons.The Mg-Zn-Caternary MG has the characteristics of low corrosion rate and uniform corrosion which rises an extensive attention for biomedical applications.However,the critical size of the Mg-Zn-CaMG is only a few millimeters,which limits their practical application in clinical.In this article,we prepared Mg₆₅Zn₃₀Ca₅ thin film metallic glass(TFMG)on the polyethylene terephthalate(PET)material by magnetron sputtering technology for surface modification.Accordingly,we got sight into the biocompatibility of Mg-Zn-CaMG and discussed the feasibility of Mg-Zn-CaTFMG for coating on biological inert materials.The research content is as following:By means of XRD diffraction,SEM and EDS analysis,we revealed that the as-prepared Mg-Zn-Cafilm had an amorphous structure and displayed a corresponding composition which was close to the applied target.The electron probe was used to observe the cross-section of the film,revealing the film deposition rate parallel to the target surface was approximately 3?m/h,and the film deposition rate perpendicular to the target surface was around 1.7?m/h.The bonding force was measured via drawing method,indicating a high bonding force of?559.2 N/cm²between the Mg-Zn-CaTFMG and the PET substrate.Additionally,the water contact angle measurement illustrated that the wettability of PET surface was effectively improved by coating Mg-Zn-CaTFMG.The hydrogen evolution experiment showed that the released hydrogen volume of the Mg-Zn-CaTFMG increased sharply at the initial stage and then gradually stabilized.Through XRD,SEM,EDS,and Raman spectroscopy,the structure,composition and surface groups of the corroded Mg-Zn-CaTFMG in SBFs were studied,demonstrating the generation of Zn-rich phase and the precipitation of phosphate.The Mg-Zn-Catarget material was melted-spun into amorphous ribbon.Electrochemical test revealed a higher corrosion resistance of Mg-Zn-CaMG compared with high purity Mg.Through CCK-8,living dead cell staining and flow cytometry analysis,the cell viability of osteoblasts of the Mg-Zn-CaMG extract was detected,which reflects an increased viability of osteoblasts and reduce cell apoptosis in Mg-Zn-CaMG extract.The Mg-Zn-CaTFMG with different thickness was achieved via various magnetron sputtering duration(0 h,0.5 h,1 h,and 2 h).The PET artificial ligaments were coated with these Mg-Zn-CaTFMGs for further application in the anterior cruciate ligament reconstruction of rats.The routine blood,blood biochemistry,and blood ICP tests of postoperative rats revealed that Mg-Zn-CaTFMG sputtered for different time had good blood compatibility.The gait analysis,micro-CT and MRI analysis of the knee joint were applied to discuss the histocompatibility of Mg-Zn-CaTFMG,revealing that amorphous film sputtered for 2 h can significantly improve the osseointegration of artificial ligaments.Our work not only exhibited the feasibility of preparing Mg-Zn-CaTFMG by magnetron sputtering,but also illustrated the corrosion behavior of Mg-Zn-CaTFMG in physiological solution.The dissolution sequence of metals and Mg/Caphosphate precipitation beneficial to the biocompatibility of such TFMG are deeply understood.The biocompatibility of amorphous Mg-Zn-Cawas discussed comprehensively from various aspects,such as corrosion resistance,cell compatibility,blood compatibility,and tissue compatibility.Consequently,we revealed Mg-Zn-CaTFMG is competent to a surface modification coating for bio-inert material based on in-vivo and in-vitro evaluation.