366
N. Ashwin Kumar et al.
breast cancer cells were injected in vivo for comparison of the accumulation of
nanoparticles in rodents. After 1 h of post-injection, the accumulation was higher
compared to normal chelates, and slow signals reduce due to the clearance mechanism. On the other hand, the injected chelates of Gd does not any change in tumor
contrast enhancement and they are least significant [182]. Beta cyclodextrin capped
Gd 2 O 3 NPs and linked with folic acid to target early cancer diagnosis. Contrast to
noise ration of targeted particles showed up to 5.89 within 1 h compared to nontargeted particles with 1.98 for 6 h [183]. Multifunctional capabilities with BSA
capped Gd 2 O 3 NPs loaded with cyanine showed trimodal imaging applications with
photoacoustic tomography, NIR- fluorescence and MR imaging [184].
Nanorods Gd(OH) 3 particles were developed by Yuan and his group with an
average size of 15 nm width and 100 nm length for MR imaging. Always there is
a question of toxicity issues when it comes to the anisotropic structure of particles.
Thus, they have evaluated cell cytotoxicity and histology analysis to confirm the
toxicity to show high biocompatibility. MR imaging of Gd(OH) 3 NPs showed higher
relaxivity compared to Gd-DTPA chelates. These Gd(OH) 3 NPs were accumulated
in the liver after 30 min of post-injection [185]. No significant changes in Gd(OH) 3
nanorods when tested for long term biodistribution and their cellular toxicities when
evaluated in vivo by Yang and his coworkers. But the clearance of Gd(OH) 3 nanorods
was slower in spleen compared to other organs [186]. Gadolinium oxide particles,
in combination with bismuth (BiGdO 3 ) capped with PEG have been implemented
as a radiosensitizer for cancer treatment. The effect of radiosensitizer in vivo was
determined using MRI and CT with gadolinium and bismuth and as theragnostic
agents [187]. Yeh and his coworkers synthesized hollow spherical and rhombusshaped Gd 2 O(CO 3 ) 2 nanoparticles as an MRI contrast agent. Spherical sized particles
were injected at a concentration of 0.3 mg kg
−1, and post-injection particles until
12 h started to accumulate in the liver is higher compared to the kidney. Survival of
animal was up to 4 weeks showed that particles possess negligible toxicity over the
rodents [188]. The same group developed Gd 2 O(CO 3 ) 2 nanoparticles coated with
silica/gold as hybrid nanoparticles and studied MR characteristics and photothermal
therapy with gold [189]. Few studies have synthesized Gd 2 O 3 as core and shell as
MnO and SiO 2 for enhanced MR signals and to study the toxicity compared to naked
Gd 2 O 3 NPs [190, 191].
Doping with Gd 2 O 3 NPs is another promising type of nanomaterial for cancer therapeutic and diagnostic applications. Yoon et al. synthesized Europium doped GdPO 4
nanoparticles by annealing phosphate silica nanoparticles with layered gadolinium
hydroxide nanosheets doped with europium. In vitro imaging suggested the particles are fluorescent with high MR relaxivity due to europium as luminescent centers
and gadolinium as a contrast agent [192]. Liquid pulsed laser ablation technique
aid in generation Europium doped Gd 2 O 3 nanoparticles from the Gd 2 O 3 :Eu
3+ solid
target. These nanoparticles are favorable as both optical and magnetic properties
for early detection of disease diagnosis. Focused Nd:YAG laser (1064 nm, 70 mJ)
exposed on the solid target immersed in deionized water for 15 min duration in
liquid by [193]. T 1 weighted images were acquired with the xenograft model exposed
with Gd 2 O 3 :Eu
3+ NPs was higher contrast at 35 min of post-injection and gradually
N. Ashwin Kumar et al.
breast cancer cells were injected in vivo for comparison of the accumulation of
nanoparticles in rodents. After 1 h of post-injection, the accumulation was higher
compared to normal chelates, and slow signals reduce due to the clearance mechanism. On the other hand, the injected chelates of Gd does not any change in tumor
contrast enhancement and they are least significant [182]. Beta cyclodextrin capped
Gd 2 O 3 NPs and linked with folic acid to target early cancer diagnosis. Contrast to
noise ration of targeted particles showed up to 5.89 within 1 h compared to nontargeted particles with 1.98 for 6 h [183]. Multifunctional capabilities with BSA
capped Gd 2 O 3 NPs loaded with cyanine showed trimodal imaging applications with
photoacoustic tomography, NIR- fluorescence and MR imaging [184].
Nanorods Gd(OH) 3 particles were developed by Yuan and his group with an
average size of 15 nm width and 100 nm length for MR imaging. Always there is
a question of toxicity issues when it comes to the anisotropic structure of particles.
Thus, they have evaluated cell cytotoxicity and histology analysis to confirm the
toxicity to show high biocompatibility. MR imaging of Gd(OH) 3 NPs showed higher
relaxivity compared to Gd-DTPA chelates. These Gd(OH) 3 NPs were accumulated
in the liver after 30 min of post-injection [185]. No significant changes in Gd(OH) 3
nanorods when tested for long term biodistribution and their cellular toxicities when
evaluated in vivo by Yang and his coworkers. But the clearance of Gd(OH) 3 nanorods
was slower in spleen compared to other organs [186]. Gadolinium oxide particles,
in combination with bismuth (BiGdO 3 ) capped with PEG have been implemented
as a radiosensitizer for cancer treatment. The effect of radiosensitizer in vivo was
determined using MRI and CT with gadolinium and bismuth and as theragnostic
agents [187]. Yeh and his coworkers synthesized hollow spherical and rhombusshaped Gd 2 O(CO 3 ) 2 nanoparticles as an MRI contrast agent. Spherical sized particles
were injected at a concentration of 0.3 mg kg
−1, and post-injection particles until
12 h started to accumulate in the liver is higher compared to the kidney. Survival of
animal was up to 4 weeks showed that particles possess negligible toxicity over the
rodents [188]. The same group developed Gd 2 O(CO 3 ) 2 nanoparticles coated with
silica/gold as hybrid nanoparticles and studied MR characteristics and photothermal
therapy with gold [189]. Few studies have synthesized Gd 2 O 3 as core and shell as
MnO and SiO 2 for enhanced MR signals and to study the toxicity compared to naked
Gd 2 O 3 NPs [190, 191].
Doping with Gd 2 O 3 NPs is another promising type of nanomaterial for cancer therapeutic and diagnostic applications. Yoon et al. synthesized Europium doped GdPO 4
nanoparticles by annealing phosphate silica nanoparticles with layered gadolinium
hydroxide nanosheets doped with europium. In vitro imaging suggested the particles are fluorescent with high MR relaxivity due to europium as luminescent centers
and gadolinium as a contrast agent [192]. Liquid pulsed laser ablation technique
aid in generation Europium doped Gd 2 O 3 nanoparticles from the Gd 2 O 3 :Eu
3+ solid
target. These nanoparticles are favorable as both optical and magnetic properties
for early detection of disease diagnosis. Focused Nd:YAG laser (1064 nm, 70 mJ)
exposed on the solid target immersed in deionized water for 15 min duration in
liquid by [193]. T 1 weighted images were acquired with the xenograft model exposed
with Gd 2 O 3 :Eu
3+ NPs was higher contrast at 35 min of post-injection and gradually