These magnetic properties are critical in the applications of the biomedical
and bioengineering fields.
SEM allowed the verification of morphological differences of Tbz–
Hb–GPTS–SPIONs and Hb–GPTS–SPIONs with bare SPIONs. As shown
in Fig. 3A, the globular structure of Hb has been distinguished on the
magnetic nanoparticle clutter [13]. After the binding of Tbz to Hb, the
morphology has slightly changed (Fig. 3B). Also, globular structures
have been seen on the surface due to the drug molecules. In order to receive
more direct information on the particle size and morphology, the
transmission electron microscopy (TEM) micrograph of pure SPIONs
was investigated (Fig. 3D). Observing the TEM micrograph, nanoparticles
formed dense aggregates due to the lack of any repulsive force between
the magnetic nanoparticles. This force is mainly due to the nanosize
of the SPIONs, which is about 10 ± 2 nm.