Relaxivity of Paramagnetic Complexes of Manganese and Gadolinium

Mn-Based MRI Contrast Agents: An Overview

“…Other research was focused on the improvement in the stability of the Mn complexes based on linear ligands by rigidifying the chelator. We can cite the addition of a cyclohexane ring (Mn-CDTA) [29,30] of one or two pyridine rings (Mn-PyC3A, Mn-PAADA, Mn-DPAA, Mn-DPAMeA, or Mn-DPAPhA) [31][32][33][34][35][36] or of the piperidine rings (Mn-AMPTA or Mn-AMPDA-HB) [37] (Figure 1, Table 1) forming pentadentate or hexadentate ligands. As expected, pentadentate complexes were globally less stable than hexadentate complexes whereas the increased rigidity of the chelator allowed more stable complexes to be obtained.…”

The [Dy(H2O)n(CyDTA)]− complex as an NMR paramagnetic relaxational temperature probe in an aqueous solution and bicelles

“…[1][2][3][4][5][6][7][8][9] For this purpose, gadolinium complexes with ligands such as DTPA, DOTA, EDTA and their various derivatives have been most intensively studied. [1][2][3][4][5][6] Despite the NMR studies available in the literature on various EDTA derivatives and their complexes with lanthanide cations (other than gadolinium), the paramagnetic and relaxation properties of this type of complex with dysprosium in aqueous solutions have been little studied and there are practically no studies related to the study of the behavior of these complexes in heterogeneous bicellular systems (for example, in water-lipid mixtures). Scientific interest in this type of complex is dictated by the question of their possible property of embedding into the lipid shell of bicellular systems.…”

“…Transition metal complexes with trans-1,2-diaminocyclohexane-N,N,N 0 ,N 0 -tetraacetic acid (CyDTA), which are structural analogues of EDTA, are currently of scientific interest and are being studied as promising diagnostic tools for MRI. [1][2][3][4][5][6] The CyDTA ligand itself has an obvious hydrophobic (cyclohexane moiety) and hydrophilic moiety. The presence of a hydrophobic fragment of the CyDTA anion increases the chance of incorporation of the [Ln(H 2 O) n (CyDTA)] À complex into the lipid shell compared, for example, with a similar complex [Ln(H 2 O) n (EDTA)] À .…”

“…Complexes of lanthanides (Ln) with various polydentate ligands have found applications in medicine as relaxation contrast reagents for MRI diagnostics. 1–9 For this purpose, gadolinium complexes with ligands such as DTPA, DOTA, EDTA and their various derivatives have been most intensively studied. 1–6…”

“…1–9 For this purpose, gadolinium complexes with ligands such as DTPA, DOTA, EDTA and their various derivatives have been most intensively studied. 1–6…”