Achievement

Our interdisciplinary team of physicists, chemists, biochemists, and instrument scientists is using high-energy-resolution quasielastic neutron scattering and molecular dynamics simulations to elucidate the motion of water molecules associated with single bilayer lipid membranes supported on a silicon substrate. By varying sample temperature, level of hydration, and deuteration, we have identified three different types of diffusive water motion: bulk-like, confined, and bound [1]. The motion of bulk-like and confined water molecules is fast compared to those bound to the lipid head groups (7−10 H2O molecules per lipid), which move on the same nanosecond time scale as H atoms within the lipid molecules.

1. M. Bai, A. Miskowiec, F. Y. Hansen, H. Taub, T. Jenkins, M. Tyagi, S. O. Diallo, E. Mamontov, K. W. Herwig, S.-K. Wang, Europhys. Lett., in press.