Preparation and antibacterial properties of plasma sprayed nano-titania/silver coatings

In this work, plasma sprayed nano-titania/silver coatings were deposited on titanium substrates to obtain an implant material having excellent antibacterial property. The surface characteristics of nano-titania/silver coatings were investigated by scanning electron microscopy, energy dispersive spectrometer, optical emission spectrometry and X-ray diffraction. The bioactivity of nano-titania/silver coatings was examined by simulated body fluid soaking test. The antibacterial activity against Escherichia coli was examined by bacterial counting method. The cytocompatibility and in vitro osteotoxicity was evaluated by alamarBlue™ Assay using MG-63 osteoblasts. The results showed that nano-titania/silver coatings still had good bioactivity. Silver existed homogeneously in the nano-titania coating as silver oxide and metal silver, which ensured a sustained release of silver for 28 days. The loaded silver had no obvious osteotoxicity, while showed strong inhibition against the growth of Escherichia coli.