The topologies of proparacaine (PPC) in fl-cycloclextrin (fl-CID), PPC in egg phosphaticly1choline (EPQ liposomes and PPC in fl-CD in EPC were investigated using NMR experiments (I D ROESY and saturation transfer difference (STD)). This is the first description of the STID technique applied to PPC - EPC -P-CD system, revealing that not only PPC was imbedded in EPC bilayer, but fl-CD was also interacting with liposome vesicles. These results are novel and were rationalized as the spontaneous formation of a ternary complex with some fl-CD molecules bound to external liposome vesicles surfaces. Copyright (c) 2008 John Wiley & Sons, Ltd.469832837