INFLUENCE OF A HYDROPHILIC SPACER ON THE STRUCTURE OF A PHOSPHOLIPID MONOLAYER

We present the results of thermodynamical and X-ray grazing incidence diffraction experiments performed on Langmuir monolayers of ether lipi ds with hydrophilic spacers between the glycerol backbone and the phos phatidylcholine head group: DHPC, DH-EO1-PC, and DH-EO2-PC. As a space r the oxy-ethylene group is used, which is a typical hydrophilic unit of non-ionic tensides. It turns out that the introduction of the hydro philic spacers leads to a fluidization of the monolayer and reduces th e tilt angle of the chains.