Preparation of titania coating by induction suspension plasma spraying for biomedical application

Abstract

In this work, the titania coatings were prepared using induction suspension plasma spraying (ISPS) technology with nano-anatase suspension as feed stock. The effects of spraying parameters (plasma power, suspension feed rate and reactor pressure) on the properties of the titania coatings were investigated here. The results showed that the porosity and the anatase content of the as-sprayed coatings increased while the deposition efficiency decreased, with increasing suspension feed rate and reactor pressure, and the decreasing plasma power. Among all of the parameters, the suspension feed rate had the most prominent influence on the microstructure, porosity and phase compositions of the coating. The optimum parameters for prepared titania coating with the optimal micro/nano-structured surface determined in this work were 30 kW of plasma power, 9 ml/min of feed rate and 28 kPa of reactor pressure. Evaluated biological performance of the coatings in vitro indicated that the micro/nano-structured titania coating exhibited a preferable protein adsorption in comparison to that of conventional coating sprayed by the direct current plasma and pure Ti with smooth surface. Our cell culture experiments demonstrated that the hierarchical micro/nano-structured titania coating can enhance the cell adhesion, proliferation rate, alkaline phosphatase activity and the extracellular matrix mineralization of MC3T3-E1 to a greater extent.