MONOLAYERS AND PLANAR OR CURVED BILAYERS

Monolayers and planar or curved bilayers can be considered useful models of biologic membranes. With this in perspective we report on studies performed on monolayers and bilayers of polypeptides and lipids. The results obtained show that the study of monolayers allows either the deduction of the interphasal orientation in a one-component system or the reasons of mutual solubility when mixtures are considered. In the case of bilayers and particularly of BLM, LB films and vesicles, it is possible to gain information about stability and thickness of single component bilayers as well as about the influence of the addition of a second component on these properties. The comparison between the various systems taken into consideration allows us to draw a first conclusion: the condition to form BLM and vesicles is to start from monolayers in expanded phases while the condition to form plurilayers and LB films is to start from monolayers in condensed phases.