Electrodeposition of Silk Fibroin on Metal Substrates

Silk fibroin, one of the most promising natural materials for tissue engineering, has positive interactions with the biological environment, particularly in the field of bone and cartilage regeneration. A new approach was developed to create hydrogels from water-based fibroin solutions by applying an electric field to effect protein migration and coagulation at the anode (Aluminium or Ti6Al4V alloy) of an electrochemical cell. The process was easily controlled by the voltage applied to the electrodes (3, 10, and 30 V), solution concentration (1%, 2%, 2.6% w/v), time (up to 100 s) and electrode distance (1-6 mm). The hydrogel thickness can be increased up to 60 mm and, depending on processing conditions, porous coatings or compact films can be obtained. The ability of electrodeposited fibroin hydrogels to coat metal objects with complex shape and surface morphology, together with the acclaimed properties of fibroin, makes it a promising technique to enhance the osteointegration of dental or orthopedic prostheses.