Fig. 2From: Effect of Surface Functionalization on the Cellular Uptake and Toxicity of Nanozeolite AMetabolic activity (MTT assay) of HeLa cells treated with different concentrations of unmodified and modified BaA nanozeolites for 24 h (a), 48 h (b), or 72 h (c). Data are expressed as a percent of control, mean ± SD from three independent experiments (asterisk denotes statistically significant difference from unexposed control, p < 0.05)Back to article page