prepared the nanoparticle core was labeled with
198 Au and the attached chelator on
the surface of nanoparticle labeled with
111 In, and they thoroughly traced the
198
Au
and
111 In radioactivity and concluded that in vivo degradation of the chelator on the
surface of nanoparticle due to proteolytic digestion [58]. On the other hand, Seo
et al. confirmed that extrinsically labeled radioisotope was not detached from
upconverting nanoparticle core even after the long-term journey through the
hepato-biliary tract [15]. Still, we cannot fully understand of this kind of controversy and there is far way to go to evaluate the exact fate of radiolabeled nanomaterials. However, from this point, we should keep in mind and confirm the
in vivo integrity after the radiolabeling of nanomaterials.
12.5 Applications of Radionanomedicine Prepared
by Click Chemistry
Nanomaterials labeled with different radioisotopes via either extrinsic or intrinsic
methods described above have been applied in diagnosis [59, 60], image guided
therapy [61] or radiotherapy [62–65].
12.5.1 Applied in Diagnosis
Nanoparticles could accumulate in tumor tissues either passively by EPR effects or
actively by the targeting molecules conjugated on nanoparticle surface, and thus
radiolabeled nanoparticles have been extensively investigated as diagnosis tools for
tumor detection.
In particular, nanoparticles labeled with positron emitter have been applied in the
PET imaging. Among many different positron emitted radionuclides,
18
F is the
most widely used one due to its good availability and ideal imaging characteristics.
Although the half-life time of
18 F is relatively short (110 min) compared to the slow
EPR process, application of a pretargeting strategy has demonstrated the great
potential to overcome this problem. Lee et al. [57] have recently reported an
18 F-based pretargeting strategy via SPAAC for nanoparticle-based PET imaging. In
particular, DBCO functionalized nanoparticles were administrated 24 h in advance
to allow sufficient accumulation of nanoparticles in tumor tissues before the subsequent administration of [
18 F]fluoropentaethylene glycolic azide, and the
sequentially injected [
18 F]fluoropentaethylene glycolic azide could ligate with
previously administrated DBCO functionalized nanoparticles, which resulted in the
significantly improved signal to background ratios.
Another widely used radioisotope in nanoparticles based PET imaging is
64 Cu,
and its half-life time is relatively longer (12.7 h) and closer to the physical half life
time of small nanoparticles. Therefore, nanoparticles had been directly labeled with
242
Y.-S. Lee et al.
198 Au and the attached chelator on
the surface of nanoparticle labeled with
111 In, and they thoroughly traced the
198
Au
and
111 In radioactivity and concluded that in vivo degradation of the chelator on the
surface of nanoparticle due to proteolytic digestion [58]. On the other hand, Seo
et al. confirmed that extrinsically labeled radioisotope was not detached from
upconverting nanoparticle core even after the long-term journey through the
hepato-biliary tract [15]. Still, we cannot fully understand of this kind of controversy and there is far way to go to evaluate the exact fate of radiolabeled nanomaterials. However, from this point, we should keep in mind and confirm the
in vivo integrity after the radiolabeling of nanomaterials.
12.5 Applications of Radionanomedicine Prepared
by Click Chemistry
Nanomaterials labeled with different radioisotopes via either extrinsic or intrinsic
methods described above have been applied in diagnosis [59, 60], image guided
therapy [61] or radiotherapy [62–65].
12.5.1 Applied in Diagnosis
Nanoparticles could accumulate in tumor tissues either passively by EPR effects or
actively by the targeting molecules conjugated on nanoparticle surface, and thus
radiolabeled nanoparticles have been extensively investigated as diagnosis tools for
tumor detection.
In particular, nanoparticles labeled with positron emitter have been applied in the
PET imaging. Among many different positron emitted radionuclides,
18
F is the
most widely used one due to its good availability and ideal imaging characteristics.
Although the half-life time of
18 F is relatively short (110 min) compared to the slow
EPR process, application of a pretargeting strategy has demonstrated the great
potential to overcome this problem. Lee et al. [57] have recently reported an
18 F-based pretargeting strategy via SPAAC for nanoparticle-based PET imaging. In
particular, DBCO functionalized nanoparticles were administrated 24 h in advance
to allow sufficient accumulation of nanoparticles in tumor tissues before the subsequent administration of [
18 F]fluoropentaethylene glycolic azide, and the
sequentially injected [
18 F]fluoropentaethylene glycolic azide could ligate with
previously administrated DBCO functionalized nanoparticles, which resulted in the
significantly improved signal to background ratios.
Another widely used radioisotope in nanoparticles based PET imaging is
64 Cu,
and its half-life time is relatively longer (12.7 h) and closer to the physical half life
time of small nanoparticles. Therefore, nanoparticles had been directly labeled with
242
Y.-S. Lee et al.