Fig. 2.

(a) Plot of the amount of AuNRs ingested by HepG2 cells quantified by ICP-MS versus incubation time. (b) The percentage of the remaining AuNRs in the cells after they are exposed to different AuNRs for 24 h. The feeding concentration of AuNRs is fixed at 20 μg/mL (c–e) Confocal laser microscopic observation of HepG2 cells incubated with AuNRs@DOX for (c) 4 h, (d) 12 h and (e) 24 h. The dose of AuNRs@DOX is 20 μg/mL in the cell culture medium. The cells were counterstained with lysometracker Green for the lysosomes. Column 1: AuNRs@DOX, Column 2: lysosomes, Column 3: merged images, Column 4: Magnified merged images. Scale bars are 20 μm and 5 μm, respectively.