Preparation And Performance Characterization Of Active Coating With Self-healing Surface

Magnesium(Mg)and its alloys have been selected as bone tissue replacement materials because of their excellent mechanical properties and degradable properties,to replace traditional non-degradable materials.However,as an active metal,Mg cannot meet clinical requirements due to its rapid degradation in the human body.From the perspective of surface modification,this paper alleviates the non-uniform corrosion of Mg and its alloys by applying a protective coating.A method for preparing a bioactive coating on the surface of a Mg-based medical implant is developed.The method includes a micro-arc oxidation(MAO)method,a spin coating method,and a dip-deposition method.Self-healing composition consisting of magnesium(MgO)/fluoride(F-)-doped mesoporous silica(SiO2)nanospheres,polylactic acid(F-MSNs@PLLA)/calcium dihydrogen phosphate(DCPD)degradable bioactive coating.The MAO method can be used to generate a MgO coating on the surface of the substrate that is closely combined with the substrate,which forms a very good protection for Mg and its alloys.The spin coating method is used to prepare the PLLA coating,and the F ions with degradation inhibition are loaded on the MSNs by electrostatic action,and the metal cations generated by the corrosion of the substrate form a relatively stable magnesium fluoride(MgF2),which makes the coating self-healing.The DCPD coating is prepared by the dipping method.The chemical composition of the degradable Ca-P active coating is similar to the main inorganic components in the bone matrix.Compared with the degradable inert coating,it can significantly promote the functional expression of stem-related cell attachment,proliferation and osteogenic differentiationThe experimental results show that the above-mentioned combined passive defense and self-healing dual mode protects Mg and its alloy substrate,and has a coating design concept and preparation technology with high bone integration ability,which can make the coating have a stronger effect on the substrate.The coating has a self-healing function and reduces the corrosion rate of Mg and its alloys in the human body.The corrosion resistance is pure Mg<0%F-MSNs<5%F-MSNs<10%F-MSNs<20%F-MSNs,thus providing the necessary time and mechanical support for new bone regeneration.At the same time,the above design is also a good new drug delivery method,using the unique physical and chemical properties of SiO2 to effectively control the release of curcumin.The coating prepared in this paper has excellent biological activity,which not only promotes the adhesion and proliferation of stem cells,but also facilitates the differentiation of stem cells into osteoblasts.Cell response follows 0%F-MSNs<5%F-MSNs<10%F-MSNs<20%F-MSN law.Figure[24]table[5]reference[127]...