Proton NMR relaxivity of blood samples in the presence of iron, gadolinium and dysprosium compounds

The longitudinal and transverse relaxation rates of some iron, gadolinium and dysprosium compounds have been measured on 1H in aqueous solutions and in blood as a function of molar concentrations. The different relaxation characteristics were analyzed and certain explanations concerning the molecular sources of these variations were advanced. The evidenced properties of these compounds are promising for interesting applications in medicine.