Magnetic and relaxation properties of vanadium(iv) complexes: an integrated ¹H relaxometric, EPR and computational study

Abstract

We report a detailed study of the magnetic and relaxation properties in solution of a series of oxovanadium(IV) complexes comprising the aqua ion [VO(H2O)5]2+ and [VO(ox)2]2 (ox = oxalate), [VO(nta)]...

Effect of hydration equilibria on the relaxometric properties of Gd(iii) complexes: new insights into old systems

“…Relaxometry has played a critical role in developing and characterizing contrast agents for magnetic resonance imaging (MRI) based on paramagnetic ions such as Gd( iii ), 4,7,8 Fe( iii ), 9–11 V( iv ) 12,13 or Mn( ii ). 14–16 MRI contrast agents used in clinical practice enhance image contrast by shortening the longitudinal relaxation times of water nuclei present in the tissues where the agent is distributed.…”

“…The r 1,2 values correspond to the relaxation rate enhancement effect of bulk water protons normalized to a 1 mM concentration of the paramagnetic solute, expressed in mM −1 s −1 units. 6 Relaxometry has played a critical role in developing and characterizing contrast agents for magnetic resonance imaging (MRI) based on paramagnetic ions such as Gd(III), 4,7,8 Fe (III), [9][10][11] V(IV) 12,13 or Mn(II). [14][15][16] MRI contrast agents used in clinical practice enhance image contrast by shortening the longitudinal relaxation times of water nuclei present in the tissues where the agent is distributed.…”

Redox reactions of a pyrazine-bridged RuIII(edta) binuclear complex: spectrochemical, spectroelectrochemical and theoretical studies

“…CAM-B3LYP and ωB97X-D3 have been demonstrated to work well for excited states of transition metal complexes, 40–42 and TPSS0 has been shown to be quite useful in predicting various challenging properties such as ionization energy, electron affinity, hyperfine coupling, and spin density accurately. 43–46 The functional TPSS0, CAM-B3LYP, and ωB97X-D3 calculations were compared (Fig. S10 in ESI†) and found to be consistent for each oxidation state of the investigated binuclear ruthenium complex.…”

MD Simulations to Calculate NMR Relaxation Parameters of Vanadium(IV) Complexes: A Promising Diagnostic Tool for Cancer and Alzheimer’s Disease

“…Figure 4 shows the structure of both VCs studied. Both structures present a double bond between vanadium and oxygen atoms, and the V=O group is an important region in which a non-coordinated water molecule can interact with by a hydrogen bonding interaction [55]. Hence, most of the water molecules present in the chemical medium will approach more closely to the metal atom at the center of the complexes due to the presence of the V=O group since the resulting interaction is considerably strong.…”

“…For Gd-DOTA, a commercial Gd(III)-based contrast agent, its T 1 and T 2 have a value of 0.032 and 0.025 s, respectively [52,53]. For Gd-DTPA, also one of the most common contrast agents, the T 2 value is 0.020 s [46,50,55]. Then, the VC1 showed to be a potential longitudinal and transversal MRI probe, being more effective than Gd-DOTA and Gd-DTPA, with superior relaxation times.…”