Partition of fatty acids and fluorescent fatty acids into membranes

Abstract

The membrane/water partition of free fatty acids, of a fluorescent analog and of chlorpromazine into plasma membranes from lymphoma, platelets, red cells and liposomes of egg phosphatidylcholine was measured. Three different methods were used as follows: hygroscopic desorption (Conrad M. J., and Singer, S. J., 1979); (Conrad, M. J., and Singer, S. J., 1981) centrifugation and fluorescence titration. Partition coefficients for chlorpromazine and all fatty acid/membrane combinations were in the range 102-105. No significant partition difference was observed between liposomes and plasma membranes. Fatty acids and chlorpromazine can readily partition into artificial and cell plasma membranes.