Effect of Sonication on the Structure of Lecithin Bilayerst

The properties of dipalmitoyllecithin vesicles of varying sizes have been compared employing proton and S1P nuclear magnetic resonanee spectroscopy and dilatometry. These studies indicate that small vesicles of about 250 A in diameter are inherently disordered and that the well-known spectral differences generally observed for vesicles of different curvatures such as lecithin multilayers and sonicated bilayers arise from variations in the molecular packing of phospholipid molecules in the bilayer phase.