Elemental microanalysis of a particle in lung tissue by electron spectroscopic imaging (ESI, three window method), demonstrating that the nanoparticles (arrows) consists of titanium, adapted from . The first image (A), taken at 0 eV, shows the structural details; it is slightly shifted as compared to the images used for elemental microanalyses (B-D). For elemental microanalysis, three images are taken: two below the element-specific edge in order to extrapolate a background image, at ΔE = 390eV (not shown) and ΔE = 440eV (B), respectively, and one image within the maximum of the element specific signal at ΔE = 464eV (L2,3 edge of titanium) (C). The net titanium signal (D) is calculated by subtraction of the extrapolated background image from the titanium specific signal. ESI images have reversed contrast as solely inelastically scattered electrons are used with an energy loss producing a dark field image. Hence, the obtained image reflects the titanium distribution in white pixels. Bar: 500 nm.