“9.61x6.69” b2815 Tissue Engineering and Nanotheranostics
Magnetic Nanohybrids for Magnetic Resonance Imaging 137
employed in multifunctional systems such as PTT and MRI. The
designed probe Fe 5 C 2 coated by (DSPE–PEG–NH 2 ) conjugated with
affinity proteins ZHER2:342 for ovarian-cancer targeting. The affinity
proteins such as ZHER2:342 are very effective for ovarian-cancer tar-
geting.^42 The temperature increment graph of Fe 5 C 2 using NIR laser
radiation (λ = 808 nm, 2 W cm−2) exhibited heat which is higher than
AuNRs (aspect ratio of 3.5) and Resovist (Fig. 24(a)) as shown in
Fig. 24.^108 Also, MRI relaxation time r2 (311.94 mM–1s–1) was greater
than Resovist 173.95 mM–1s–1. MR images (Fig. 24(b)) of Fe 5 C 2 also
showed excellent imaging enhancement as compared to Resovist.
Further, Fe 5 C 2 nanoparticles conjugated with PEG and ZHER2:342
were examined for in vivo T 2 –MRI contrast agent. The nanoparticles
were injected into SK–OV–3 tumor-bearing mice and performed T 2
weighted MR images shown in Fig. 24(c) before and after intrave-
nous injection. In both groups, imaging intensities were dropped at
the tumor sites which can be seen in the pseudocolor pictures. The
MRI results demonstrated that the Fe 5 C 2 coupled with ZHER2:342 probe
attained efficient in vivo tumor ablation and excellent MRI without
any other effect. Later, they employed prepared magnetic hybrids in
photothermal therapy and the results are shown in Fig. 24(d). MRI
results reveal obvious tumor ablation between the untreated mice and
mice with treated Fe 5 C 2 –ZHER2:342 nanoparticles. This research high-
lights the significant potential of Fe 5 C 2 MHNPs as multifunctional
probes for MR imaging and PTT of cancer.
Xiangyang Shi et al. took one step forward in the synthesis of
magnetic gold nanostars Mau–NSs to obtain trimodality purposes.34,35
Fe 3 O 4 @Au hybrid nanostars functionalized using polyethyleneimine
(PEI) were successfully used in T 2 MRI contrast agent and photother-
mal therapy of cancer. They investigated the r2 MR transverse relaxa-
tion time of Mau–NSs which is about 144.39 mM–1s–1 (Fig. 25)
greater than many reported values. The signal intensity enhancement
in the MRI can be seen in the inset of Fig. 25(a) which might be
related to the aggregation of iron oxide nanoparticles.
Next, in vivo MR imaging was analyzed using the BALB/c
mice bearing HeLa tumor with respect to time. The prepared nano-
flowers ([Fe] = 5.0 mM, 0.1 mL) in aqueous solution were injection
