Fig. 2
Effect of agglomeration state of Rubipy-SiO2 NPs on the level of cell uptake. The cellular uptake of Rubipy-SiO2 NPs was quantified by flow cytometry after 3 h exposure of CaCo-2 cells to 200 µg/ml of 30 and 80 nm Rubipy-SiO2 NPs either added to complete medium immediately before exposure (grey bars) or pre-incubated in complete medium for 24 h at 37 °C (black bars)