A Novel Porous Coating Method of Commercially Pure Titanium Using Silk Fibroin and <scp>UV</scp> Light for Biomedical Implant Applications

Surface coatings for titanium implants have been actively investigated using numerous materials to improve biocompatibility and osteointegration. This study developed a novel porous coating method for titanium implants; we coated commercially pure titanium (Cp-Ti) using the photocurable properties of methacrylated silk fibroin (SilMA). Surface morphologies and alloying chemistry after coating were investigated by scanning electron microscopy (SEM) and EDS, while the biocompatibility of the SilMA-coated Cp-Ti was evaluated by the CCK-8 and live/dead assays. With various SilMA concentrations, uniform and strong SilMA coatings were obtained by UV light for both thin and thick coating methods. A universal mechanical testing machine evaluated the mechanical properties of SilMA coating. The interface adhesive strength of the coating taken by advanced centrifugal measurement was enhanced as the SilMA concentration increased. Cell cytotoxicity test results for 1, 3, 5, and 7 days revealed no toxic behavior in human dermal fibroblast cells. Cells on the SilMA-coated Cp-Ti revealed a higher proliferation and survival rate than those on the titanium without coating. These results show that this versatile coating method offers a tightly adhered bioactive coating of silk fibroin on titanium implants, demonstrating the potential for a universal coating method for use in a wide range of biomedical applications.