Cyclen lanthanide-based micellar structures for application as luminescent [Eu(iii)] and magnetic [Gd(iii)] resonance imaging (MRI) contrast agents.

The synthesis of coordinatively unsaturated tetra-substituted 1,4,7,10-tetraazacyclododecane (cyclen) lanthanide complexes is described; these structures, possessing hydrophobic (C12-alkyl) tails and hydrophilic head groups, self-assemble into supramolecular micellar structures in aqueous solution, and hence can be utilised as novel contrast agents for MRI.