A composite coating of calcium alginate and gelatin particles on Ti6Al4V implant for the delivery of water soluble drug.

A composite coating on Ti6Al4V implant was prepared from alginate and gelatin particles through a dip-coating method to control the release of the water soluble drug gentamicin and improve the surface properties of the implant. Gentamicin was dissolved in the coating or bonded to gelatin particles through Schiff base reaction. The drug release experiments in vitro showed that about 10% of gentamicin was released within 0.5 h, the release lasted for 10 days, and the release from the composite coating was dependent on the pH value. The composite coating could induce the formation of apatite on the coating surface, which was fully covered after 7 days immersing in SBF solution. In addition, Ti6Al4V plate with the composite coating had excellent antibacterial activity against Staphylococcus aureus. All of the results provided the possibility that this composite coating might be applied as a controlled release system to deliver the water soluble drug, and as a bioactive, biodegradable layer on the bio-inert implant surface to induce the formation of apatite and actively bond to the surrounding tissue in vivo. (c) 2008 Wiley Periodicals, Inc.