Fig. 4.

Cytotoxicity effect of hydroxyurea and hydroxyurea loaded into gold nanoparticle complex on MCF-7 cell line after 48 h of incubation. Results are presented as mean ± 5 % error of three independent experiments. Improving drug efficiency in nanoparticle form compared with free form is also evident in this figure. Furthermore it illustrates cytotoxicity reduction by decreasing drug concentration which was valid for concentrations higher than 80 μM. In lower concentrations of 80 μM (i.e. gold NP concentration was about 3 μM), it showed an increasement in cytotoxicity in spite of reducing drug concentration