Water isotope effect on the lipidic cubic phase: Heavy water-Induced interfacial area reduction of monoolein-Water system

作者：Takahashi Hiroshi^*; Jojiki Kotaro

来源：Chemistry and Physics of Lipids, 2017, 208: 52-57.

DOI：10.1016/j.chemphyslip.2017.09.001

• Bicontinuous cubic phase
• Monoolien
• Surface area
• Triply periodic minimal surface

Heavy water (D2O) affects various functions of cells and living things. In order to gain fundamental insight into the molecular mechanism on biological effects of heavy water, D2O-effects on fully hydrated monoolein (MO) systems were investigated from the structural viewpoints. At room temperature, the MO fully hydrated by pure light water (H2O) forms a bicontinuous cubic (Pn3m) phase, and then, the Pn3m cubic phase transforms into an inverted hexagonal (H-II) phase at about 90 degrees C. Temperature-scan X-ray diffraction measurements showed that substitution of D2O for H2O lowers the Pn3m-to-H-II phase transition temperature and reduces the lattice constants of both phases. The structural analysis of the Pn3m phase using the diffraction intensity data indicated that D2O reduces the surface occupied area of MO at the interface by 12% in comparison with H2O. This change is probably due to the difference of the strength of hydrogen bond.

• 出版日期2017-11