Gd(iii) chelates for MRI contrast agents: from high relaxivity to “smart”, from blood pool to blood–brain barrier permeable

MedChemComm ◽  
2012 ◽  
Vol 3 (5) ◽  
pp. 552 ◽  
Author(s):  
Chang-Tong Yang ◽  
Kai-Hsiang Chuang
Keyword(s):  
Contrast Agents ◽  
Blood Brain Barrier ◽  
Blood Pool ◽  
Mri Contrast Agents ◽  
Brain Barrier ◽  
Mri Contrast ◽  
Blood Brain ◽  
High Relaxivity

scholarly journals Brain Redox Imaging Using Blood—Brain Barrier-Permeable Nitroxide MRI Contrast Agent

2008 ◽  
Vol 28 (6) ◽  
pp. 1165-1174 ◽  
Author(s):  
Fuminori Hyodo ◽  
Kai-Hsiang Chuang ◽  
Artem G Goloshevsky ◽  
Agnieszka Sulima ◽  
Gary L Griffiths ◽  
...  
Keyword(s):  
Cerebral Cortex ◽  
Contrast Agent ◽  
Contrast Agents ◽  
Brain Tissue ◽  
Blood Brain Barrier ◽  
Mri Contrast Agents ◽  
Mri Contrast Agent ◽  
Brain Barrier ◽  
Mri Contrast ◽  
Blood Brain

Reactive oxygen species (ROS) and compromised antioxidant defense may contribute to brain disorders such as stroke, amyotrophic lateral sclerosis, etc. Nitroxides are redox-sensitive paramagnetic contrast agents and antioxidants. The ability of a blood—brain barrier (BBB)-permeable nitroxide, methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl (MC-P), as a magnetic resonance-imaging (MRI) contrast agent for brain tissue redox imaging was tested. MC-P relaxation in rodent brain was quantified by MRI using a fast Look-Locker T1-mapping sequence. In the cerebral cortex and thalamus, the MRI signal intensity increased up to 50% after MC-P injection, but increased only by 2.7% when a BBB-impermeable nitroxide, 3CxP (3-carboxy-2,2,5,5,5-tetramethylpyrrolidine-1-oxyl) was used. The maximum concentrations in the thalamus and cerebral cortex after MC-P injection were calculated to be 1.9±0.35 and 3.0±0.50 mmol/L, respectively. These values were consistent with the ex vivo data of brain tissue and blood concentration obtained by electron paramagnetic resonance (EPR) spectroscopy. Also, reduction rates of MC-P were significantly decreased after reperfusion following transient MCAO (middle cerebral artery occlusion), a condition associated with changes in redox status resulting from oxidative damage. These results show the use of BBB-permeable nitroxides as MRI contrast agents and antioxidants to evaluate the role of ROS in neurologic diseases.

Blood-Pool and Targeting MRI Contrast Agents: From Gd-Chelates to Gd-Nanoparticles

2012 ◽  
Vol 2012 (12) ◽  
pp. 1924-1933 ◽  
Author(s):  
Gang Ho Lee ◽  
Yongmin Chang ◽  
Tae-Jeong Kim
Keyword(s):  
Contrast Agents ◽  
Blood Pool ◽  
Mri Contrast Agents ◽  
Mri Contrast

ChemInform Abstract: High-Relaxivity MRI Contrast Agents: Where Coordination Chemistry Meets Medical Imaging

ChemInform ◽  
2009 ◽  
Vol 40 (3) ◽  
Author(s):  
Eric J. Werner ◽  
Ankona Datta ◽  
Christoph J. Jocher ◽  
Kenneth N. Raymond
Keyword(s):  
Coordination Chemistry ◽  
Medical Imaging ◽  
Contrast Agents ◽  
Mri Contrast Agents ◽  
Mri Contrast ◽  
High Relaxivity

scholarly journals Nano-assemblies of cationic mPEG brush block copolymers with gadolinium polyoxotungstate [Gd(W5O18)2]9− form stable, high relaxivity MRI contrast agents

Nanoscale ◽  
2018 ◽  
Vol 10 (15) ◽  
pp. 7270-7280 ◽  
Author(s):  
Joanne Ly ◽  
Yuhuan Li ◽  
Mai N. Vu ◽  
Bradford A. Moffat ◽  
Kevin S. Jack ◽  
...  
Keyword(s):  
Block Copolymer ◽  
Block Copolymers ◽  
Contrast Agents ◽  
Mri Contrast Agents ◽  
Good Stability ◽  
Mri Contrast ◽  
High Relaxivity

Nano-assemblies of gadolinium polyoxotungstate and cationic mPEG brush block copolymer demonstrated good stability and enhanced relaxivity at physiological pH.

scholarly journals A Photocleavable Contrast Agent for Light-Responsive MRI

2020 ◽  
Vol 13 (10) ◽  
pp. 296
Author(s):  
Friederike Reeßing ◽  
Sèvrin E. M. Huijsse ◽  
Rudi A. J. O. Dierckx ◽  
Ben L. Feringa ◽  
Ronald J.H. Borra ◽  
...  
Keyword(s):  
Contrast Agent ◽  
Contrast Agents ◽  
Mri Contrast Agents ◽  
Mri Contrast Agent ◽  
Whole Body ◽  
Spatiotemporal Resolution ◽  
Mri Contrast ◽  
High Relaxivity ◽  
Vis Spectroscopy ◽  
Clinical Mri

Thanks to its innocuousness and high spatiotemporal resolution, light is used in several established and emerging applications in biomedicine. Among them is the modulation of magnetic resonance imaging (MRI) contrast agents’ relaxivity with the aim to increase the sensitivity, selectivity and amount of functional information obtained from this outstanding whole-body medical imaging technique. This approach requires the development of molecular contrast agents that show high relaxivity and strongly pronounced photo-responsiveness. To this end, we report here the design and synthesis of a light-activated MRI contrast agent, together with its evaluation using UV–vis spectroscopy, Fast Field Cycling (FFC) relaxometry and relaxometric measurements on clinical MRI scanners. The high relaxivity of the reported agent changes substantially upon irradiation with light, showing a 17% decrease in relaxivity at 0.23T upon irradiation with λ = 400 nm (violet) light for 60 min. On clinical MRI scanners (1.5T and 3.0T), irradiation leads to a decrease in relaxivity of 9% and 19% after 3 and 60 min, respectively. The molecular design presents an important blueprint for the development of light-activatable MRI contrast agents.

Gadolinium-bearing red cells as blood pool MRI contrast agents

1998 ◽  
Vol 40 (1) ◽  
pp. 133-142 ◽  
Author(s):  
Kevin M. Johnson ◽  
Jing Zang Tao ◽  
Richard P. Kennan ◽  
John C. Gore
Keyword(s):  
Contrast Agents ◽  
Blood Pool ◽  
Mri Contrast Agents ◽  
Red Cells ◽  
Mri Contrast

scholarly journals Predicting Breakdown of the Blood-Brain Barrier in Multiple Sclerosis without Contrast Agents

2012 ◽  
Vol 33 (8) ◽  
pp. 1586-1590 ◽  
Author(s):  
R.T. Shinohara ◽  
J. Goldsmith ◽  
F.J. Mateen ◽  
C. Crainiceanu ◽  
D.S. Reich
Keyword(s):  
Multiple Sclerosis ◽  
Contrast Agents ◽  
Blood Brain Barrier ◽  
Brain Barrier ◽  
Blood Brain

Supramolecular aggregates from polyacrylates and Gd(iii)-containing cationic surfactants as high-relaxivity MRI contrast agents

2015 ◽  
Vol 6 (9) ◽  
pp. 1521-1526 ◽  
Author(s):  
Yingying Chen ◽  
Qin Zhu ◽  
Yu Tian ◽  
Weijun Tang ◽  
Fei Pan ◽  
...  
Keyword(s):  
Contrast Agents ◽  
Cationic Surfactants ◽  
Mri Contrast Agents ◽  
Sodium Acrylate ◽  
Mri Contrast ◽  
Molecular Weights ◽  
High Relaxivity ◽  
Assembly Behavior ◽  
Supramolecular Aggregates

The assembly behavior of narrowly dispersed poly(sodium acrylate) (PAAS) of different molecular weights with Gd(iii)-containing cationic metallosurfactants (MS) was investigated by DLS, TEM and relaxivity plotting.

Water-Soluble Gadofullerenes:  Toward High-Relaxivity, pH-Responsive MRI Contrast Agents

2005 ◽  
Vol 127 (2) ◽  
pp. 799-805 ◽  
Author(s):  
Éva Tóth ◽  
Robert D. Bolskar ◽  
Alain Borel ◽  
Gabriel González ◽  
Lothar Helm ◽  
...  
Keyword(s):  
Contrast Agents ◽  
Mri Contrast Agents ◽  
Water Soluble ◽  
Ph Responsive ◽  
Mri Contrast ◽  
High Relaxivity
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