In Vitro Toxicity Evaluation of Engineered Cadmium-Coated Silica Nanoparticles on Human Pulmonary Cells

Figure 5

Representative images of randomly selected microscopic fields of the colonies formed after 10 consecutive days exposure to increasing concentrations (0.05–100 μg/mL) of Cd-SiO₂NPs, CdCl₂, and SiO₂NPs. SiO₂NP colonies showed similar patterns at the all tested doses to the control (control data not shown). Few colonies with reduced size compared to control were observed at the lower concentrations (0.05–10 μg/mL) of Cd-SiO₂NPs and CdCl₂, while there was a total inhibition of the colonies at the higher tested doses (25–100 μg/mL) for both Cd-SiO₂NPs and CdCl₂. (Scale bar: 600 μm).