Interaction of channel-blocking bispyridinium compounds with supported phospholipid layers.

The interaction of phospholipid monolayers of dioleoyl phosphatidylcholine (DOPC) on mercury electrodes with bispyridinium compounds is reported in this paper. The interaction is related to the modification of the capacitance-potential plot and in particular of two well defined phase transitions of the phospholipid monolayer. The order of the extent of interaction of the test compounds with the monolayer can be related to their structure and is: P65>Toxogonin>BPE>HS6>TMB4>HI6>BPT>P2S. The penetration of the compound into the monolayer depends on potential. At potentials more negative than the occurrence of the two phase transitions, the test compounds penetrate further and disrupt the monolayers. At more positive potentials this effect is reversed.