Study of the interaction between lanthanide ions and a supported bilayer lipid membrane by cyclic voltammetry and ac impedance

The interaction of lanthanide ions with a supported bilayer lipid (1,2-dimyristoyl-sn-glycero-3-phosphatidylcholine) membrane (sBLM) was investigated by cyclic voltammetry and ac impedance spectroscopy in this paper. Lanthanide can affect the conformation of the supported bilayer lipid membrane and cause pore formation. Through the pores, Fe(CN)63−/4− can reach the electrode surface and show its redox behaviour. Furthermore the redox currents of Fe(CN)63−/4− increased with increasing concentration of lanthanides and leveled off at 1.2 μM for Eu3+. The interaction ability of three lanthanides with sBLM follows the sequence: Eu3+>Tb3+>La3+.