Figure 4

SEM images of different MNPs bound on GMR sensor surface.
(a) Control; (b) 20 nm MNPs; (c) 30 nm MNPs; (d) 30 nm MNPs (Zoom out); (e) 50 nm MNPs; (f) 100 nm MNPs. All the scale bars are 1 μm.
SEM images of different MNPs bound on GMR sensor surface.
(a) Control; (b) 20 nm MNPs; (c) 30 nm MNPs; (d) 30 nm MNPs (Zoom out); (e) 50 nm MNPs; (f) 100 nm MNPs. All the scale bars are 1 μm.