Fig. 1. (A) Schematic representation of the influence of substrate stiffness on cell endocytosis of 120 nm and 360 nm Cy5-labelled silica particles. Cell spreading and focal adhesion maturation on tissue culture polystyrene is abrogated when cultures are performed on softer fibronectin-coated PDMS 10 : 1 and fibronectin-coated PDMS 40 : 1. Increased internalization of particles was observed for cells on more mechanically compliant substrates. (B) Transmission electron micrograph of silica nanoparticles (dTEM = 120 nm). Corrected time course dynamic light scattering measurements performed in water and supplemented RPMI at 0 h and 6 h indicate particle stability. (C) Transmission electron micrograph of silica particles (dTEM = 360 nm). Corrected time course dynamic light scattering measurements performed in water and supplemented RPMI at 0 h and 6 h indicate no particle aggregation. Scale bars represent 2 μm.
