ROLE OF HYDROPHOBIC AND HYDROPHILIC INTERACTIONS OF ORGANOTIN AND ORGANOLEAD COMPOUNDS WITH MODEL LIPID-MEMBRANES

The present study was conducted to clarify the mechanism of toxicity o f organic compounds using lipid model membranes (liposomes and planar lipid membranes). The compounds studied were trialkyltin and trialkyll ead chlorides, dialkyltin dichlorides and some inorganic forms of thos e metals. Two different (anionic and cationic) detergents were also us ed in the experiments to change the surface properties of liposomes. A s a measure of interaction between the compounds studied and model mem branes were the release of liposome bound praseodymium and the change in stability of planar membranes under the influence of those compound s. On the basis of the results obtained it was postulated that the mec hanism of interaction between tin- and leadorganics and model lipid me mbranes is a combination of different factors featuring interacting si des. The most important properties determining the behaviour of organi c compounds in the interaction were lipophilicity and polarity of diff erent parts of the organics and the steric arrangement they can take i n the medium. On the other hand, the surface potential of the lipid bi layer and the environment of the lipid molecules, that play a signific ant role in the availability of the lipid bilayer to the organics, wer e important factors in the interaction.