镍钛合金光催化高级氧化表面改性与生物相容性 

Advanced oxidation in UV/H₂O₂ photocatalytic system could results in the formation of a titanium oxides film depleted of Ni on NiTi shape memory alloy (SMA). In this work, the biocompatibility of advanced oxidized NiTi SMA was systematically investigated by contact angle test, platelet adhesive test and MTT cytotoxicity test. It was found that the wettability of NiTi SMA could be improved by photocatalytic oxidation. The number of platelets on surface modified NiTi SMA was decreased and moreover the phenomena of distortion and congregativeness of platelets were controlled, thus the possibility of thrombas formation was depressed. As a result, the hemocompatibility of NiTi SMA was improved. The relative growth rate (RGR) of fibroblasts of the modified NiTi SMA was higher than that for the chemically polished one. The cell proliferation in the vicinity of the modified NiTi SMA was well and the cells combined with the sample naturally. All those suggest that the cytocompatibility of the surface modified NiTi SMA was improved too. The results indicate that advanced oxidation in UV/H₂O₂ photocatalytic system is a promising way to improve the biocompatibility of NiTi SMA.