Nuclear magnetic relaxation dispersion studies of water‐soluble gadolinium(iii)‐texaphyrin complexes

  title={Nuclear magnetic relaxation dispersion studies of water‐soluble gadolinium(iii)‐texaphyrin complexes},
  author={Carlos Geraldes and A. Dean Sherry and Patrick Vallet and Fr{\'e}d{\'e}ric Maton and Robert N. Muller and Tarak D. Mody and Gregory W. Hemmi and Jonathan L. Sessler},
  journal={Journal of Magnetic Resonance Imaging},
Water proton 1/T1 nuclear magnetic relaxation dispersion (NMRD) profiles were measured for a water‐soluble gadolinium(III) texaphyrin (Gd‐tex) complex as a function of temperature and in the presence and absence of 5% human serum albumin (HSA). Upon dissolving the complex in water (0.259 mM), the water relaxivity values decreased with time but remained higher than those of free Gd3+(aq)at all fields. Concurrent measurements of free Gd3+ using metallochromic dyes indicated that demetallation of… Expand
High-Relaxivity contrast agents for magnetic resonance imaging based on multisite interactions between a beta-cyclodextrin oligomer and suitably functionalized GdIII chelates.
The results reported in this work show that tightly assembled adducts formed by trisubstituted GdIII complexes and a beta-CD multimer (Poly-beta-CD, d.p. ca. 12) may represent very interestingExpand
Structure, stability, dynamics, high-field relaxivity and ternary-complex formation of a new tris(aquo) gadolinium complex.
A new versatile method to unravel the geometric and dynamic molecular factors that explain the high-field relaxivities has been developed and uses a small, uncharged non-coordinating probe solute, the outer-sphere relaxivity of which mimics that of the water proton. Expand
Structures of MRI Contrast Agents in Solution
Contrast agents for magnetic resonance imaging are mainly Gd3+ complexes of octadentate polyaminopolycarboxylates and one water molecule in the first coordination sphere of the metal ion. Both theExpand
A novel series of complexones with bis- or biazole structure as mixed ligands of paramagnetic contrast agents for MRI.
Improving significantly the relaxivities of reference compounds such as Gd(III)EDTA (5.2, 5.6) or Gd (III)DTPA (4.30, 4.30). Expand
Metal coordinated pyrrole-based macrocycles as contrast agents for magnetic resonance imaging technologies: Synthesis and applications
Abstract The number of scientific reports on the field of imaging in biomedical sciences is rising massively, with the emergence of “noninvasive” in vivo imaging technologies, of which MagneticExpand
Temperature dependence of water diffusion pools in brain white matter
Water diffusion in brain tissue can now be easily investigated using magnetic resonance (MR) techniques, providing unique insights into cellular level microstructure such as axonal orientation. TheExpand
Myelin-targeted, texaphyrin-based multimodal imaging agent for magnetic resonance and optical imaging.
The synthesis and application of multimodal myelin-specific imaging agents for light microscopy and magnetic resonance imaging are described and it is demonstrated that the complexes are retained in white matter structures and enable detection of myelin. Expand
Texaphyrin Conjugates. Progress Towards Second Generation Diagnostic and Therapeutic Agents
Cancer, despite significant research efforts, remains a major health issue and the second leading cause of death, exceeded only by heart disease [1]. In both, cancer and heart disease, the ability toExpand
Strategies for Target-Specific Contrast Agents for Magnetic Resonance Imaging.
The advantages and limitations of these two targeting strategies with respect to translation from in vitro to in vivo imaging while focusing on advances from the last ten years are described. Expand
Challenges for molecular neuroimaging with MRI
Key challenges associated with expanding the repertoire of successful molecular neuroimaging approaches are discussed, including recent efforts to enhance relaxivity of conventional longitudinal relaxation time and transverse relaxation time MRI contrast agents, as well as strategies that involve amplifying molecular signals or reducing endogenous background influences. Expand


Nuclear magnetic relaxation dispersion profiles of aqueous solutions of a series of gd(nota) analogs
Those complexes which either tended to form aggregates in solution or gave evidence for multiple averaged solution structures showed broad, near Lorentzian linewidths which were clearly not dominated by the electron spin relaxation time (τs), which is in reasonable agreement with those derived from their NMRD profiles. Expand
Tissue distribution and stability of metalloporphyrin MRI contrast agents
Upon intravenous injection into athymic mice bearing subcutaneous human colon carcinoma xenografts, MnTPPS provided enhanced relaxation of the tissue water in several excised mouse tissues, notably kidney, liver, and tumor. Expand
Characteristics of gadolinium-DTPA complex: a potential NMR contrast agent.
The combination of strong proton relaxation, in-vivo stability, rapid urinary excretion, and high tolerance favors the further development and the potential clinical application of gadolinium-DTPA as a contrast enhancer in magnetic resonance imaging. Expand
The anomalous relaxivity of Mn3+(TPPS4)
Mn3+(TPPS4) may be one of a class of molecules with properties particularly favorable for use as contrast‐enhancing agents in magnetic resonance imaging, and the theory of relaxation by magnetic dipolar interactions is established, in a form appropriate for small paramagnetic solute molecules. Expand
Preclinical Evaluation of Gadolinium (III) Texaphyrin Complex: A New Paramagnetic Contrast Agent for Magnetic Resonance Imaging
Gadolinium (III) texaphyrin complex appears to be an effective and safe MRI contrast agent. Expand
A new lipophilic gadolinium chelate as a tissue‐specific contrast medium for MRI
The preclinical studies suggest Gd‐EOB‐DTPA's clinical role as being a hepatobiliary contrast agent for MRI, and the diagnostic dose is considerably lower than the amount of Magnevist used in abdominal imaging. Expand
Magnetic field dependence of solvent proton relaxation rates induced by Gd3+ and Mn2+ complexes of various polyaza macrocyclic ligands: Implications for NMR imaging
It is found that, over the field range in which NMR imaging is currently being done, different symmetries of otherwise similar chemical ligands can alter 1/T1 of solvent protons by factors of up to three. Expand
The importance of nuclear magnetic relaxation dispersion (NMRD) profiles in MRI contrast media development.
Observation of the relaxivity of MRI contrast media over a wide range of magnetic fields is not only necessary for predicting their efficiency at any field but also compulsory for understanding andExpand
Solution and solid-state characterization of europium and gadolinium Schiff base complexes and assessment of their potential as contrast agents in magnetic resonance imaging
Two lanthanide Schiff base macrocyclic complexes, LnAM(OAc){sub 2}Cl{center dot}4H{sub 2}O (Ln = Eu, Gd; HAM - HexaAzaMacrocycle = C{sub 22}H{sub 26}N{sub 6}), have been characterized in view of theExpand