Fig. 2. Characterization of encapsulin-produced magnetic iron oxide nanocomposites (eMIONs).

a Representative TEM image of encABC (Inset: DLS of encABC). Scale bar: 100 nm. b, c Isosurface representation of reconstructed nanoparticles color-coded according to the radial distance from the center (given in Å): b view from the outside; c cutaway view of the internal structure. d Schematic diagram of the biomimetic synthesis of eMIONs and the heat emission under alternative magnetic field (AMF). e Representative TEM (scale bar: 100 nm) image of eMIONs (inset images I to IV: biomimetic synthesis time at 0, 1, 3, and 6 h, respectively). Scale bar: 50 nm. f HRTEM and corresponding FFT pattern (inset) of eMIONs nanocrystals, corresponding to {102}-faceted FeO and {311}-faceted Fe₃O₄. g XPS analyses of eMIONs. h The results of VSM analysis of eMIONs and fMIONs. i Schematic illustration of eMIONs and fMIONs for magnetic-to-thermal conversion under AMF. One of three repetitions with similar results is shown here for a, e, and f.