Fig. (5) Intercalation of the lipopolyamines into LPS aggregates (A), phosphatidylcholine liposomes (B), and phosphatidylserine liposomes (C) in Förster resonance energy transfer spectroscopic (FRET) experiments. As sensitive measure of incorporation the ratio of donor to acceptor intensity I_D/I_A is plotted versus time. The LPAs were added to the lipid aggregates after 50 s. Data were generated in two independent experiments (two coloured lines are shown for each compound).