Abstract:
A three-dimensional-phospholipid monolayer with tunable
molecular structure was created on the surface of oil nanodroplets
from a mixture of phospholipids, oil, and water. This simple
nanoemulsion preparation technique generates an in situ prepared
membrane model system with controllable molecular surface properties
that resembles a lipid droplet. The molecular interfacial structure of such
a nanoscopic system composed of hexadecane, 1,2-dihexadecanoyl-snglycero-3-phosphocholine
(DPPC), and water was determined using
vibrational sum frequency scattering and second harmonic scattering
techniques. The droplet surface structure of DPPC can be tuned from a
tightly packed liquid condensed phase like monolayer to a more dilute one that resembles the liquid condensed/liquid expanded
coexistence phase by varying the DPPC/oil/water ratio. The tunability of the chemical structure, the high surface-to-volume
ratio, and the small sample volume make this system an ideal model membrane for biochemical research
