Titania nanotube delivery fetal bovine serum for enhancing MC3T3-E1 activity and osteogenic gene expression

Titania nanotube (TNT) delivery of fetal bovine serum (FBS) was conducted on titanium (Ti) to enhance bone tissue repair. Scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) showed FBS increased the tube wall thickness and decreased the tube diameter. Attenuated total reflectance Fourier transform infrared further confirmed that FBS completely covered the TNT and changed the surface composition. Water contact angle tests showed TNT/FBS possessed hydrophilic properties. Compared to original Ti, the TNT/FBS group had more attached osteoblasts after 2h and enhanced filopodia growth at 0.5h. Significantly, more osteoblasts were also observed on TNT/FBS after 7d culturing. FBS was released steadily from TNT; about 70% of FBS had been released at 3d and 90% at 5d, as shown by the bicinchoninic acid method. TNT/FBS also enhanced subsequent osteoblast differentiation and gene expression; the quantum real-time polymerase chain reaction test showed that TNT/FBS up-regulated alkaline phosphatase and osteocalcin gene expression at 7d and 14d. Therefore, TNT/FBS delivered sustained in situ nutrition and enhanced osteoblast activity and osteogenic gene expression.