Amphiphilic star-shaped oligomers are produced by anionic polymerization of ethylene oxide (EO) using per-2,3-di-O-heptyl-beta-(or gamma)cyclodextrins as initiators a versatile way of synthesizing artificial channels bearing one polyEO branch per glucose unit. The behavior of the amphiphilic molecules in lipid membranes is studied by electrical measurements, which confirms the formation of transient, well-defined dimeric ionic channels (see figure).