Abstract
The present study has reviewed (i) how to classify the water molecules in multilamellar dispersions of lipid-water system on the basis of the ice-melting behavior as revealed by heating differential scanning calorimetry (DSC) and (ii) how to estimate the numbers of nonfreezable interlamellar and freezable interlamellar and bulk water molecules in this system from enthalpies of the ice-melting endotherms. Furthermore, by applying the calorimetric method, the numbers of the individual water molecules in different bonding modes were estimated for varying water contents of three lipid systems of different head groups (phosphatidylcholine, phosphatidylethanolamine and phosphatidylglycerol), and then used to construct water distribution diagrams of these systems. By comparing the resultant diagrams, the difference in the mode of hydration of three lipid bilayers, limited or infinite, was discussed.
