In-situ introduced bio-active coatings inside 3D printed porous TC4 alloy for bone implant application

Collagen-loaded layer double hydroxide (LDH) flakes were in-situ incorporated into plasma electrolytic oxidized (PEO) coating, with the aim of enhancing the biocompatibility of 3D printed porous TC4 alloy for bone implantation. The morphology evolution, corrosion behavior and in-vitro biocompatibility were investigated, and the results indicated that the morphology of PEO layer was affected by both the composition of Ti matrix and incorporation of collagen-loaded LDH flakes. The loading of collagen reduced the pore dimension but increased the porosity of outer PEO layer. Long term corrosion resistance was enhanced by PEO treatment, and the incorporation of collagen remarkably improved osteogenesis, cell proliferation and differentiation ability. An in-situ collagen-loaded PEO coating with considerable corrosion resistance and excellent biocompatibility was suggested for modification of 3D printed implants.