Gain of a 500-fold sensitivity on an intravital MR Contrast Agent based on an endohedral Gadolinium-Cluster-Fullerene-Conjugate: A new chance in cancer diagnostics

“…1 and 2) and Al 2 O 3 are widely used in catalysis, 3,4 Au nanorods have been studied for selective release of drugs, 5 Rh nanoparticles (NPs) confined inside carbon nanotubes (CNTs) have been studied for ethanol production from syngas, 6 and Co NPs inside CNTs have been studied for tailoring the band gap of CNTs. 7 Furthermore, magnetic iron-oxide NPs and rare-earth atoms have been investigated as contrast agents for magnetic resonance imaging, 8,9 which is important for cancer therapy.…”

Section: Introductionmentioning

confidence: 99%

Encapsulation of small magnetic clusters in fullerene cages: A density functional theory investigation within van der Waals corrections

Tereshchuk

Silva

2012

Phys. Rev. B

View full text Add to dashboard Cite

The encapsulation of magnetic transition-metal (TM) clusters inside carbon cages (fullerenes, nanotubes) has been of great interest due to the wide range of applications, which spread from medical sensors in magnetic resonance imaging to photonic crystals. Several theoretical studies have been reported; however, our atomistic understanding of the physical properties of encapsulated magnetic TM 3d clusters is far from satisfactory. In this work, we will report general trends, derived from density functional theory within the generalized gradient approximation proposed by Perdew, Burke, and Ernzerhof (PBE), for the encapsulation properties of the TM m @C n (TM = Fe, Co, Ni; m = 2−6, n = 60,70,80,90) systems. Furthermore, to understand the role of the van der Waals corrections to the physical properties, we employed the empirical Grimme's correction (PBE + D2). We found that both PBE and PBE + D2 functionals yield almost the same geometric parameters, magnetic and electronic properties, however, PBE + D2 strongly enhances the encapsulation energy. We found that the center of mass of the TM m clusters is displaced towards the inside C n surfaces, except for large TM m clusters (m = 5 and 6). For few cases, e.g., Co 4 and Fe 4 , the encapsulation changes the putative lowest-energy structure compared to the isolated TM m clusters. We identified few physical parameters that play an important role in the sign and magnitude of the encapsulation energy, namely, cluster size, fullerene equatorial diameter, shape, curvature of the inside C n surface, number of TM atoms that bind directly to the inside C n surface, and the van der Waals correction. The total magnetic moment of encapsulated TM m clusters decreases compared with the isolated TM m clusters, which is expected due to the hybridization of the d-p states, and strongly depends on the size and shape of the fullerene cages.

show abstract

“…[58][59][60][61] Cells labeled with these paramagnetic agents produce signal hyperintensities in T1w images. Because clinical Gd agents (i.e., Gd-DTPA and Gd-DOTA) have low relaxivities (T2 relaxivity of 6 mmol −1 s −1 and T1 relaxivity of 4 mmol −1 s −1 ) many groups are developing Gd-based agents with higher relaxivity 59 or are conjugating Gd chelates to carriers to deliver a higher payload. 60 Overall, Gd agents are not as readily incorporated into cells, work best at lower magnetic fields, and have relatively low relaxivities that decrease further upon cell internalization.…”

Section: Volume 5 September/october 2013mentioning

confidence: 99%

Tracking and evaluation of dendritic cell migration by cellular magnetic resonance imaging

Dekaban

Hamilton²,

Fink

et al. 2013

WIREs Nanomed Nanobiotechnol

View full text Add to dashboard Cite

Cellular magnetic resonance imaging (MRI) is a means by which cells labeled ex vivo with a contrast agent can be detected and tracked over time in vivo. This technology provides a noninvasive method with which to assess cell-based therapies in vivo. Dendritic cell (DC)-based vaccines are a promising cancer immunotherapy, but its success is highly dependent on the injected DC migrating to a secondary lymphoid organ such as a nearby lymph node. There the DC can interact with T cells to elicit a tumor-specific immune response. It is important to verify DC migration in vivo using a noninvasive imaging modality, such as cellular MRI, so that important information regarding the anatomical location and persistence of the injected DC in a targeted lymph node can be provided. An understanding of DC biology is critical in ascertaining how to label DC with sufficient contrast agent to render them detectable by MRI. While iron oxide nanoparticles provide the best sensitivity for detection of DC in vivo, a clinical grade iron oxide agent is not currently available. A clinical grade (19) Fluorine-based perfluorcarbon nanoemulsion is available but is less sensitive, and its utility to detect DC migration in humans remains to be demonstrated using clinical scanners presently available. The ability to quantitatively track DC migration in vivo can provide important information as to whether different DC maturation and activation protocols result in improved DC migration efficiency which will determine the vaccine's immunogenicity and ultimately the tumor immunotherapy's outcome in humans.

show abstract

Gain of a 500-fold sensitivity on an intravital MR Contrast Agent based on an endohedral Gadolinium-Cluster-Fullerene-Conjugate: A new chance in cancer diagnostics

Cited by 52 publications

References 57 publications

Structure, Dynamics, and Computational Studies of Lanthanide‐Based Contrast Agents

Structure, Dynamics, and Computational Studies of Lanthanide‐Based Contrast Agents

Encapsulation of small magnetic clusters in fullerene cages: A density functional theory investigation within van der Waals corrections

Tracking and evaluation of dendritic cell migration by cellular magnetic resonance imaging

Contact Info

Product

Resources

About