Thermotropic and barotropic phase behavior of dihexadecylphosphatidylcholine bilayer membrane

✍ Scribed by Shoji Maruyama; Hitoshi Matsuki; Hayato Ichimori; Shoji Kaneshina

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 491 KB
• Volume: 82
• Category: Article
• ISSN: 0009-3084
• DOI: 10.1016/0009-3084(96)02573-x

✦ Synopsis

The temperature (T)-pressure (P) phase diagram of the ether-linked dihexadecylphosphatidylcholine (DHPC) multilamellar vesicles was constructed by the method of high-pressure optical density. The DHPC membrane at ambient pressure undergoes the pretransition (at 33.6°C) from the interdigitated gel (L/~I) phase to the ripple gel (P)~) phase, and succeedingly the main transition (at 44.4°C) from the P)~ phase to the liquid crystal (L~) phase. Since the slope of the T-P diagram for the pretransition, 0.316 K MPa 1 is larger than that for the main transition, 0.242 K MPa 1, the phase boundary between P~ and L/~I phases disappeared at high pressure above 130 MPa. A triple point among L/jI, P~ and L~ phases was found at 130 MPa and 74.5°C. Difference in phase diagrams between the ether-linked and ester-linked phospholipid bilayer membranes has been elucidated.