Figure 2

TEM micrographs revealing different core characteristics of investigated magnetite MNP. TEM micrographs of OD15 (A), MF66 (B), fluidMAG-D (100 nm) (C), fluidMAG/12-D (100 nm) (D), fluidMAG-D (150 nm) (E), nanomag-D (130 nm) (F), and fluidMAG-D (200 nm) (G) MNP. Magnification = ×75000 (B, D, F). Magnification = ×160000 (A, C, E, G).