Osteogenic
differentiation as evaluated by osteogenesis-related
gene expression and ALP activity. (A–D) Relative expression
levels of ALP, RUNX2, COL1, and BMP2 at day 7, 14, and 21. (E) ALP staining
results of the cells after culturing with different PEEK scaffolds
for 14 days. (F) Relative ALP activity of cells on the different PEEK
scaffolds at days 7 and 14. *P < 0.05 and **P < 0.01 compared with PEEK-S; #P < 0.05 and ##P < 0.01 compared
with PEEK-300. The images share 100 μm scale bar (E). For each
group, n = 3.