, 4:3 | Cite as

Lipids at the air–water interface

  • Alfred Blume
Lecture Text


Lipids are important natural chemical compounds, as they comprise the major component in biological membranes. Biological membranes are composed of lipids in a bilayer structure and proteins incorporated into the bilayers or bound to the bilayer surface. Due to the amphiphilic nature of lipids, they self-assemble in aqueous solution into a variety of lyotropic phases, the most important one being the lamellar phase made up of stacks of lipid bilayers separated by water layers. The bilayer structure can be easily produced by dispersing lipids in water. Lipids are amphiphilic structures built up of a polar headgroup and one or two hydrophobic alkyl chains. They are, therefore, surface active and form the so-called insoluble monolayers or Langmuir films at the air–water interface. These monolayers resemble half of a lipid bilayer and are, therefore, widely used as model systems for bilayer membranes. In this review, the properties and the phase behavior of phospholipid monolayers, as well as the techniques used for studying these monolayers will be described. In addition, examples for the information gained using different techniques will be shown.


Lipid monolayers Langmuir trough Monolayer characterization methods Infrared reflection absorption spectroscopy Epifluorescence microscopy 



This work was supported by Grants from the Deutsche Forschungsgemeinschaſt (DFG), the state of Saxonia-Anhalt, the Phospholipid Research Center, Heidelberg, Germany, and Boehringer Ingelheim GmbH and Co, Ingelheim, Germany. I want to express my gratitude to all members of my group for their contributions to the research results presented here in this review.


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Authors and Affiliations

  1. 1.Institute of Chemistry–Physical ChemistryMartin-Luther-University Halle-WittenbergHalle(Saale)Germany

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