Low temperature electrophoretic deposition of porous chitosan/silk fibroin composite coating for titanium biofunctionalization

The electrophoretic deposition (EPD) technique can be used to fabricate functional coating on titanium implant. In this study, chitosan/silk fibroin composite coatings were deposited onto titanium substrates via EPD at about 4 degrees C, which was recommended for protein stability and cell viability. We tested the characterization and cell behavior of the hydrogel coatings. The obtained gelatinous coatings had a similar macroporous structure with pore size ranging from 100 to 300 mu m. The silk fibroin content in the coatings increased proportionally with the increase of the silk fibroin in the electrophoretic solutions. The shear and tensile bond strength of the coatings to titanium substrates increased with the increasing silk fibroin content. In vitro biological tests indicated that chitosan/silk fibroin composite coatings had better cellular affinity than pure chitosan coatings. Therefore, the low temperature EPD is an advanced technique for preparing functional coating on titanium surface and chitosan/silk fibroin composite coatings are promising candidates for loading bioactive protein and appropriate cells.