Figure 5.

Cell viability in Raw264.7 after 2 hours and 24 hours of exposure to absolute numbers of 5 nm and 15 nm Au NPs.

Notes: Cells were exposed to 1.00×10⁹, 1.00×10¹⁰, and 1.00×10¹¹ Au NPs and evaluated by MTT assay. The data show the percent of living cells normalized to untreated control (±SEM, n=9). Statistically significant differences from the C− were determined by the Student’s t-test (*P<0.05). There were no statistically significant differences between the same number of 5 nm and 15 nm Au NPs.

Abbreviations: Au NP, gold nanoparticle; C+, positive control (10 μM hydrogen peroxide); C−, negative (untreated) control; h, hours; MTT, methylthiazol tetrazolium; SEM, standard error of the mean.