Fig. 3
From: Brain iron accumulation in neurodegenerative disorders: Does air pollution play a role?
Fe speciation is illustrated using STEM imaging. Box A: TEM Grid Fe Speciation. a STEM image shows Fe3O4 nanoparticle agglomerate with corresponding elemental maps for Fe (b) and O (c). High resolution STEM (d–e) shows polycrystalline Fe3O4 domains and a thin hematite (Fe2O3) rim approximately 1–2 nm wide with low density (red arrows). Electron diffraction patterns are illustrated for magnetite core (f) and hematite rim (g). Box B: Fe nanoparticles identified in olfactory bulb. a Two regions, marked with yellow square, where Fe particles translocated to olfactory bulb. A magnified view is shown in (b) and further magnified in (c–e) with corresponding elemental maps for Fe and O distribution. f STEM image illustrating the location of two isolated exogenous magnetite (Fe3O4) particles near a corpora amylacea body with copious endogenous Fe particle accumulation “ferritin NP”. g–l further magnification of the Fe3O4 that show no Fe2O3 rims. j–l ferritin NP at higher magnification in the STEM images with corresponding elemental map for Fe (m). ELLS analysis of ferritin NP of the region marked in j with a yellow square. Correspondingly, Fe3O4 was detected in olfactory bulb from an Fe-exposed brain