Biophysical studies of the interaction of peptides with model membranes provide a simple yet
effective approach to understand the transport of peptides and peptide based drug carriers across
the cell membrane. Herein, the authors discuss the use of self-assembled monolayers fabricated
from the full membrane-spanning thiol (FMST) 3-((14-((40-((5-methyl-1-phenyl-35-(phytanyl)oxy-
yl)oxy)tetradecyl)oxy)-2-(phytanyl)oxy glycerol for ultrahigh vacuum (UHV) based experiments.
UHV-based methods such as electron spectroscopy and mass spectrometry can provide important
information about how peptides bind and interact with membranes, especially with the hydrophobic
core of a lipid bilayer. Near-edge x-ray absorption fine structure spectra and x-ray photoelectron
spectroscopy (XPS) data showed that FMST forms UHV-stable and ordered films on gold. XPS
and time of flight secondary ion mass spectrometry depth profiles indicated that a proline-rich amphipathic
cell-penetrating peptide, known as sweet arrow peptide is located at the outer perimeter
of the model membrane.