Fig. 4
Effect of Gd2O3:Eu3+ nanoparticles on cell viability. Human embryonic kidney cells 293T and human breast cancer cells T-47D were cultured in increasing concentration ofunmodified (N1-bare), APTMS coated (N2-APTMS), and folic acid-functionalized Gd2O3:Eu3+ nanoparticles (N3-FA) for 24 or 48 h, before measuring cell viability. The experiment was run in triplicate and OD570 nm is expressed as % of control (0 µg/ml nanoparticles). Results are expressed as the mean ± SEM *P < 0.05; **P < 0.01; ***P < 0.001; and ****P < 0.0001 obtained using 2-way ANOVA with a Tukey post-test