Phase behaviour of phospholipid membranes under high pressure

Abstract The Raman and infrared spectra of aqueous 1,2-diacyl phosphatidylcholines have been measured as a function of pressure. The liquid crystalline phase of these aqueous systems transforms into a series of five gel phases upon the elevation of external pressure. The phase states and the changes in the structural and dynamic properties at the critical pressures are reviewed and analysed from the spectroscopic results, particularly regarding the driving force for the phase modifications. The mechanism for the complicated phase behavior of the subgel phase in these systems is also discussed.