English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  Coordination Properties of GdDO3A-Based Model Compounds of Bioresponsive MRI Contrast Agents

Gunduz, S., Vibhute, S., Botar, R., Kalman, F., Toth, I., Tircsó, G., et al. (2018). Coordination Properties of GdDO3A-Based Model Compounds of Bioresponsive MRI Contrast Agents. Inorganic Chemistry, 57(10), 5973-5986. doi:10.1021/acs.inorgchem.8b00473.

Item is

Basic

show hide
Item Permalink: http://hdl.handle.net/21.11116/0000-0001-7CAB-4 Version Permalink: http://hdl.handle.net/21.11116/0000-0001-7F76-D
Genre: Journal Article

Files

show Files

Locators

show
hide
Locator:
Link (Any fulltext)
Description:
-

Creators

show
hide
 Creators:
Gunduz, S1, 2, Author              
Vibhute, S1, 3, Author              
Botar, R, Author
Kalman, FK, Author
Toth, I, Author
Tircsó, G, Author
Regueiro-Figueroa, M, Author
Esteban-Gomez, D, Author
Platas-Iglesias, C, Author
Angelovski, G1, 2, Author              
Affiliations:
1Max Planck Institute for Biological Cybernetics, Max Planck Society, ou_1497794              
2Research Group MR Neuroimaging Agents, Max Planck Institute for Biological Cybernetics, Max Planck Society, ou_2528691              
3Department Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, Max Planck Society, ou_1497798              

Content

show
hide
Free keywords: -
 Abstract: We report a detailed characterization of the thermodynamic stability and dissociation kinetics of Gd3+ complexes with DO3A derivatives containing a (methylethylcarbamoylmethylamino)acetic acid (L1), (methylpropylcarbamoylmethylamino)acetic acid (L2), 2-dimethylamino-N-ethylacetamide (L3), or 2-dimethylamino-N-propylacetamide (L4) group attached to the fourth nitrogen atom of the macrocyclic unit. These ligands are model systems of Ca2+- and Zn2+-responsive contrast agents (CA) for application in magnetic resonance imaging (MRI). The results of the potentiometric studies (I = 0.15 M NaCl) provide stability constants with log KGdL values in the range 13.9–14.8. The complex speciation in solution was found to be quite complicated due to the formation of protonated species at low pH, hydroxido complexes at high pH, and stable dinuclear complexes in the case of L1,2. At neutral pH significant fractions of the complexes are protonated at the amine group of the amide side chain (log KGdL×H = 7.2–8.1). These ligands form rather weak complexes with Mg2+ and Ca2+ but very stable complexes with Cu2+ (log KCuL = 20.4–22.3) and Zn2+ (log KZnL = 15.5–17.6). Structural studies using a combination of 1H NMR and luminescence spectroscopy show that the amide group of the ligand is coordinated to the metal ion at pH ∼8.5, while protonation of the amine group provokes the decoordination of the amide O atom and a concomitant increase in the hydration number and proton relaxivity. The dissociation of the complexes occurs mainly through a rather efficient proton-assisted pathway, which results in kinetic inertness comparable to that of nonmacrocyclic ligands such as DTPA rather than DOTA-like complexes.

Details

show
hide
Language(s):
 Dates: 2018-05
 Publication Status: Published in print
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Method: -
 Identifiers: DOI: 10.1021/acs.inorgchem.8b00473
BibTex Citekey: GunduzVBKTTREPA2018
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: Inorganic Chemistry
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: -
Pages: - Volume / Issue: 57 (10) Sequence Number: - Start / End Page: 5973 - 5986 Identifier: -