“9.61x6.69” b2815 Tissue Engineering and Nanotheranostics
Multifunctional Nanomaterials for Cancer Theranostics 247
photoacoustic imaging guided NIR photothermal therapy (PTT).^295
Cheng et al. used PEGylated WS2 nanosheets as a multifunctional
theranostic agent for in vivo dualmodal CT/photoacoustic imaging
guided PTT.^296
5.3. Computed Tomography
CT is a diagnostic imaging technique based on the fundamental
principle that the density of the tissue passed by the Xray beam
measured from the calculation of the attenuation coefficient. Thus,
anatomical information of a 3D image with high spatial resolution
can be clearly provided by CT owing to the differences in Xray
attenuation of biological tissues such as bone, muscle, fat, water, and
air. Because the atomic number of noble metal nanomaterials is
higher than that of nonionic iodine preparation, the CT diagnostic
effect by gold nanoparticles and so on is better. Wei et al. reported a
simple noninjection method to fabricate uniformly sized pure Bi
nanoparticles. The Bi nanoparticles obtained had highly uniform
size, excellent monodispersity, and impressive antioxidant capacity.
After being modified with oligosaccharide, the “sweet” Bi nano
probe with comfortable patient experience and favorable biocompat
ibility was successfully used in CT visualization of gastrointestinal
tract in detail.^297 Motiei et al. developed a nanoparticlebased
approach, utilizing glucosefunctionalized gold nanoparticles as a
metabolically targeted CT contrast agent.^298 The approach showed
specific tumor targeting and had successfully distinguished between
cancer and inflammatory processes in a combined tumorinflamma
tion mouse model, due to dissimilarities in angiogenesis occurring
under different pathologic conditions.^298
5.4. Radionuclide Imaging
Radionuclide imaging technique mainly includes PET and SPECT.
PET utilizes more expensive radionuclides and their emitted γ rays
with a shorter halflife to produce images. Commonly used radio
nuclides have^111 In,^64 Cu, and^18 F. Compared with SPECT, the