Polymerization of Lipid and Lysolipid Like Diacetylenes in Monolayers and Liposomes

The bilayer type lipid membrane has a variety of important functions that are necessary in order to sustain life. A lot of these functions have been studied with artificial model membranes such as black lipid membranes (BLM) or liposomes. A great disadvantage of all these models is their instability — BLM for instance can only exist for minutes or hours and only under the presence of water. Therefore, it was the aim of this work to produce simple model membranes that can retain their structure under a variety of test conditions. The route chosen to obtain such membranes was through the polymerization of lipid and lysolipid like molecules in monolayers at the gas-water interface or in liposo…

Surface characterization of functional poly(diacetylene) and poly(butadiene) mono- and multilayers

The surface properties of Langmuir-Blodgett mono- and multilayers of a variety of amphiphilic poly(diacetylene)s and poly(butadiene)s were investigated by contact angle, streaming potentialζ, ellipsometry, and X-ray photoelectron spectroscopic (XPS) measurements. Captive air and octane angles varied between approximately 60° and 105° for hydrophobicx-layers and 31° to 46° for hydrophilic surfaces depending on the particular head group, whereas advancing angles determined via the vertical plate method are considerably higher. Negative streaming potentials were obtained for all surfaces. Positively charged monolayers yielded less negativeζ- potential values (−28 mV) than negatively charged (−…

Polymerizable phospholipid analogues--new stable biomembrane and cell models.

Polymeric monolayers and liposomes as models for biomembranes

Polymer chemists as poachers in foreign grounds? Why not? Macromolecular chemistry has become a mature science with all advantages and handicaps of a well-established scientific discipline: many heights are conquerred and the harvest is abundant, but adventures and the future might be elsewhere. Besides, in these times of bottomed out industrial profits in common plastics, future polymer chemistry cannot be limited to repetitive improvement of already successful mass polymers but should rather expand into neighboring fields of material science as well as life science where “polymer thinking” might help to overcome difficulties. — First hesitant steps on the bridge towards membrane biology h…

Polymeric Oriented Monolayers and Multilayers as Model Surfaces

All living cells are surrounded by a lipid bilayer membrane in which a variety of proteins (e.g., enzymes) are embedded (fluid mosaic model; Figure 1). Phospholipids and cholesterol represent the major part of the lipids of a biomembrane. Figure 2 illustrates the structure of some typical amphiphilic membrane components with hydrophobic alkyl chains and hydrophilic head groups. The amount of protein in biological membranes varies between 40 and 60%(3); however, in highly specialized membranes values between 20% (myelin sheath of nerve axons; electrical isolator) and 75% (mitochondrial inner membrane; enzyme system of the respiratory chain) may occur. Furthermore, the incorporation of protei…