Fig. 5.

HAADF-STEM images. a Overall view of bacteria free of PtNPs (control). The arrow points to large electron-dense granules composed of polyphosphate and manganese and the arrowhead points to diffuse light grey regions associated with the nucleoid. The scale bar is 1 µm. b–g Representative images of the control (b–d) and cells incubated with PtNPs (e–g). Arrows point to small circular bright objects containing atoms with high atomic number that correspond to PtNPs. The scale bars are 0.5 µm