Fig. 2

Upper panel: spectrum of optical extinction from a suspension of macrophages exposed to 400 µM Au pLys-coated gold nanorods for 24 h (circlets), together with its numerical fit (line) and corresponding decomposition into an empirical contribution from the macrophages plus an analytical approximation of the plasmonic band of a population of gold nanorods (shadows) [65, 66]. This decomposition was processed to quantify the amount of gold per cell. Lower panel: mass of gold taken up per cell for murine macrophages treated with a dosage of 400 µM Au, during incubation with gold nanorods (full symbols) as well as after their medium was replaced with fresh SFM without particles (empty symbols). The vertical dashed line denotes the timepoint when the replacement took place. Solid and dotted lines are guides to the eye only