New Phase Formation of Dimyristoylphosphatidylglycerol Bilayer-Assembly with Sodium or Ammonium Ions: Gelation Phenomena in the Lamellar Liquid Crystals Aged in Water

摘要

The thermal properties of lamellar phases of dimyristoylphosphatidylglycerol (DMPG) bilayer-assemblies with counter ions of Na~- and NH_4~+ are remarkably different. However, these lamellar phases of NaDMPG and NH_4DMPG in water have been found to undergo a new gelation in common when they are aged for a couple of weeks beow 40 deg C. The new gel phases named Gel-2 reversibly changed to the corresonding liquid crystal phases (LC-2) at transition temperatures (T_I0 of 40 deg C for NaDMPG and 44 deg C for NHi_4DMPG, respectively.