Magnetically-coated silica nanospheres for dual-mode imaging at low ultrasound frequency

Figure 1 Overview of typical scanning electron microscopy images for each prepared nanoparticle contrast agents sample. Scale bars in the first row of pictures are 1 mm in 160 nm SiNS diameter, 3 mm in 330 nm SiNS diameter, and 5 mm in 660 nm SiNS diameter. SiNSs: Silica nanospheres; Pure: Uncoated SiNSs; FePt-IO: Ferrum platinum-iron oxide; IO: Iron oxide.