Characterisation of phospholipid layers at liquid interfaces. 3. Relaxation of spreading phospholipid monolayers under harmonic area changes

摘要: Abstract A modified Langmuir trough with an oscillating barrier was used to investigate the relaxation behaviour and dilational rheology of spread phospholipid monolayers l -α-dipalmitoyl phosphatidylcholine (DPPC) -α-dimyristoyl phosphatidylethanolamine (DMPE). The harmonic area perturbation initiates processes in monolayer provides information on elasticity viscosity a monolayer. In coexistence region, is dominated by domain exchange. This exchange visualised Brewster angle microscopy at oscillation frequency compression/expansion cycles 0.1 Hz. single phase regions, considered be result rearrangements orientations aliphatic chains. Close pure condensed phase, significant increase between stress strain arises corresponding viscosity. Possible origins this are discussed.