[Characterization and osteogenic activity of FSP-modified TiNbTaZr/Zn].

To investigate whether Ti-35Nb-2Ta-3Zr/Zn (TNTZ/Zn) composite material processed by friction stir processing has osteogenic activity.Zn was added to the surface of TNTZ alloy by friction stir processing. The control group was TNTZ(TNTZ without FSP), the experimental groups was FSP(FSP without Zn), TNTZ/Zn-0.5 (0.5 mm pre-made holes) and TNTZ/Zn-1(1 mm pre-made holes). Surface characterization was performed by scanning electron microscope and X-ray diffraction. Alkaline phosphatase(ALP) activity of co-cultured rat bone marrow stromal stem cells (BMSCs) and COL-1α, OPN and OCN gene expression were detected by real-time quantitative PCR. SAS version 8.2 software was used for data analysis.Zn nanoparticles on the surface of the TNTZ/Zn-1 group were distributed homogeneously, with a diameter range of 70-80 nm. Compared with TNTZ group, the activity of ALP in TNTZ/Zn-0.5 and TNTZ/Zn-1 groups was up-regulated (P<0.05 and P<0.01). Compared with TNTZ group, ALP, COL-1α, OPN and OCN gene expression increased in TNTZ/Zn-0.5 and TNTZ/Zn-1 group, and the difference was statistically significant (P<0.05).Through FSP, Zn can be successfully integrated onto the surface of TNTZ alloy with nano-scale microstructures. TNTZ/Zn composite material can effectively induce bone formation and is a potential implant material.