Quantification of Internalized Silica Nanoparticles via STED Microscopy

Figure 7

SEM micrographs of A549 cells incubated for 5 h with Si-25-FD and Si-85-FD in serum-free medium. SiO₂ concentrations of 1 and 10 μg mL⁻¹ Si-25-FD induced no changes in cell morphology. After exposure to 100 μg mL⁻¹ Si-25-FD (a) A549 cells are round in cell shape compared to unexposed cells (ctr). At a concentration of 10 μg mL⁻¹ SiO₂ and higher, both particle sizes formed agglomerates and bound to the cell membrane. Incubation with 1, 10, or 100 μg mL⁻¹ Si-85-FD particles (b) induced no changes in cell morphology.

(a)

(b)