ALTERATION OF THE PASSIVE ELECTRICAL-PROPERTIES OF ADRIAMYCIN-TREATED RED-CELL MEMBRANE DEDUCED FROM DIELECTRIC-SPECTROSCOPY

The interaction of adriamycin (ADR) molecules with human erythrocytes has been investigated by radiowave dielectric spectroscopy complemented with electron microscopy methods to elucidate the extent of modification induced by this antitumoural drug in the passive electrical properties of the membrane. The electrical parameters, i.e. the membrane conductivity sigma-s and the membrane permittivity epsilon-s, deduced by analysis of the conductivity dispersion curves at radiowave frequencies demonstrate that ADR molecule is incorporated in the lipid bilayer, modifying the transport properties of the overall membrane. Moreover, a two-shell dielectric model provides further indication that the most relevant alterations occur in the innermost layer of the membrane. This finding is shown to be fully consistent with the observed ultrastructural alterations.