Fig. 3

a Cytotoxicity of GNWs and GNSs in the absence of radiation, measured by ATP assay at 24 h. 4T1 cells were incubated with GNWs and GNSs at different concentrations (3.125–500 μg Au/mL) for 24 h. PBS treated cells were studied as a control. ***p < 0.001. b Hydroxyl radical generation under RT in the presence of GNWs or GNSs (50 μg/mL), measured by APF assay