LANGMUIR-BLODGETT MONOLAYERS AND MULTILAYERS OF GRAMICIDIN-A AND LIPIDS AS MEMBRANE-MIMETIC MODELS

Monolayers and multilayers of Gramicidin A (channel-forming protein in biological membranes and its mixtures with methyl stearate and ethyl palmitate were studied in order to prepare mimetic membranes for the s elective ion transport using Langmuir-Blodgett (LB) films. Monolayers of Gramicidin A were spread at different temperatures and on different subphases containing Na+, K+ and Ca2+ ions, and ions were investigate d using FT-IR-ATR spectra of LB multilayers to detect conformational c hanges at the interface. The dependence of the values of molecular are as and the collapse pressure as a function of molar fractions of Grami cidin A in mixtures with methyl stearate and ethyl palmitate, proved t hat the components showed complete and ideal miscibility. The FT-IR-AT R spectra of LB monolayers and multilayers of these mixtures were also reported.