The state of phospholipid membranes in aqueous solutions of physiologically active substances with different electric potentials
The physicochemical and electrical characteristics of Langmuir monolayers made from distearoylphosphatidylcholine (DSPC), formed on the surface of water or aqueous solutions of physiologically active compounds (PACs) with different electrical potential, was studied. It is determined, that the electric potential of the subphase was influenced on the surface potential of the examined Langmuir monolayers. Experimentally shown that an increase of positive potential of surfactants solutions reduces surface pressure phase transition «liquid»-«solid» and reduce the mechanical strength of membranes up to destruction studied monolayers, and increasing the negative potential of surfactants solutions accompanied by an increase of the surface pressure of such a phase transition. Also was found, that under the influence of PACs solutions may be excite of membrane depolarization or increase their negative potential. Based on these results, a suggestion regarding the mechanism of interaction of PAC with the lipid matrix.