Cell culture.
Osteoblast-like cells from rat calvaria (MC3T3-E1) cells were cultured in sterile cell culture plates containing α-minimal essential medium (α-MEM) with 10% heat-inactivated fetal bovine serum (FBS) (Biowest, Riverside, MO, USA), 2 mM L-glutamine and 10 U/mL penicillin/streptomycin (Gibco, Grand Island, NY, USA) in a humidified 95% air/5% CO2 incubator at 37 °C. When the cells reached sub-confluence, they were harvested and sub-cultured. The cell suspension (5.0 × 104 cells) was slowly dripped onto the substrates (non-coated, SF-coated and TiBP-SF coated) in 48-well plates. Three replicates of each sample were tested during the culture period. Plates were shaken using gentle agitation for 10 min and were then incubated for 3 h at 37 °C. Then, 0.5 mL of medium was added along the side of each well.