Stability of monomolecular films of archaebacterial tetraether lipids on silicon wafers: a comparison of physisorbed and chemisorbed monolayers.

The monomolecular organisation of symmetric, chemically modified tetraether lipids caldarchaeol-PO(4) was studied using Langmuir film balance, ellipsometry, and atomic force microscopy (AFM). Solid silicon wafer substrates were modified to hydrophobic, hydrophilic, and amino-silanised surfaces; and Langmuir-Blodgett (LB)-films were transferred onto each. LB-caldarchaeol-PO(4) films were subjected to further rinsing with organic solvent and additional physical treatments, to compare their resistance and stability on chemisorbed (amino-silanised) and physisorbed (hydrophobic and hydrophilic) surfaces.

AFM and ellipsometric studies on LB films of natural asymmetric and symmetric bolaamphiphilic archaebacterial tetraether lipids on silicon wafers.

The monomolecular organisation of the natural asymmetric and symmetric bolaamphiphilic (archaebacterial tetraether lipids) was studied using a combination of Langmuir film balance, ellipsometry, and atomic force microscopy (AFM). Monolayer films were transferred onto silicon wafer substrates. After transfer of the lipids onto several kinds of silicon wafer substrates (hydrophobic, hydrophilic, and amino-silanised), the monolayer films were further investigated by ellipsometry and AFM in order to determined whether bolaamphiphiles are oriented differently at the water-air interface, including "horseshoe" and "upright" configurations.