Figure 4.

Effect of TiO₂ nanotube coatings enriched with the different concentrations of silver nanoparticles (1wt% and 1.5wt%; TNT/Ag) on the L929 cell adhesion (after 24 h; (a)) and proliferation (after 72 h; (b)) on the nanotube surface detected by the MTT assay. The absorbance values are expressed as means ± standard error mean (S.E.M.) of three experiments. Asterisk indicates significant differences between the cells incubated with the respective nanotubes coating doped by different concentrations of Ag (1% vs. 1.5%; * p < 0.05, ** p < 0.01). Hash mark indicates significant differences between the cells incubated with TiO₂ nanotubes or Ti plates (TNT or Ti) in comparison to the cells incubated with respective TNT or Ti coatings doped by silver nanoparticles (TNT/Ag or Ti/Ag; # p < 0.05, ## p < 0.01, ### p < 0.001).