Hydroxyapatite/Chitosan-Metformin Composite Coating Enhances The Biocompatibility And Osteogenic Activity Of AZ31 Magnesium Alloy

Objective: In this study,the corrosion resistance,osteogenic and antiinflammatory properties of magnesium alloys were enhanced by fabricating Hydroxyapatite(HA)/Chitosan(CS)-Metformin(MF)coatings.Methods: A hydroxyapatite/chitosan-metformin(AZ31/HA/CS-MF)composite coating was prepared on AZ31 magnesium alloy by hydrothermal treatment.The structure and morphology of the composite coating were characterized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),Energy dispersive spectroscopy(EDS),and Scanning electron microscopy(SEM).Electrochemical tests and hydrogen evolution experiments were carried out to evaluate the corrosion resistance of the AZ31/HA/CS-MF composite coating.At the same time,the cytocompatibility,osseointegration ability and anti-inflammatory activity of the AZ31/HA/CS-MF composite coating were studied.Results: The findings revealed that the AZ31/HA/CS-MF coating sample has better in vitro corrosion resistance than AZ31 and the AZ31/HA coating.In vitro cell culture experiments have shown that the AZ31/HA/CS-MF coating can upregulate the expression level of bone-related genes.At the same time,the AZ31/HA/CS-MF coating is more conducive to the polarization of M2 macrophages and secret anti-inflammatory cytokines.Conclusions: The findings revealed that the AZ31/HA/CS-MF composite coating exhibits excellent corrosion resistance,biocompatibility,osteogenic activity and inflammatory properties.