ABSTRACT
This chapter reviews some of the extensive literature on the hydration properties of various phospholipids. It begins with the assembly of lipid aggregates in water and some of the factors responsible for the formation of the various hydrated phospholipid phases. The chapter presents data on the amount of water imbibed by phospholipids as obtained from a variety of biophysical techniques. It explores the hydration properties of the most common membrane phospholipids, including zwitterionic and charged phospholipids, are compared, and the location of water in phospholipid bilayers and the structural effects of dehydration are detailed. It also presents an analysis of phospholipid hydration in terms of inter- and intrabilayer forces and the energetics of hydration of phospholipid bilayers. In the presence of water, phospholipids spontaneously organize into characteristic supra-molecular structures, such as spherical, disklike, or cylindrical micelles, or into bilayers and vesicles.
