Water transverse relaxation rates in aqueous dispersions of superparamagnetic iron oxide nanoclusters with diverse hydrophilic coating.

Highlights: [•] Hydrophilic coating of oleate-coated SPIONs by surfactants and triblock copolymers. [•] Self-assembly of surfactants onto oleate layer is more predominant than ligand exchange. [•] Structure of amphiphilic molecules affects clustering of SPIONs within hydrophilic coating. [•] Particular effect of outer zone versus nearest one on relaxivity of hydrophilic SPIONs. [•] Counter-ion interactions with ATP induce changes in relaxivity of surfactant-coated SPIONs. [Copyright &y& Elsevier]