Domain Patterns in Monomolecular Film Assemblies

Macro domains of micrometer size have been reported when using an ordinary microscope. The typical procedure is to use 2% of a fluorescent lipid analog, which renders visible a domain pattern. This, of course, assumes that the fluorescence moiety has no effect on the assembly structure. There is (generally) no information about the thickness of the domains. The shapes of domains are varied, and very complex (circular or near-circular domains, parallel stripes, or more irregular, wormlike, or similar kinds of structures). 

FIGURE 10.4 Cholesterol domain (consisting of 107 molecules) as studied by AFM. (a) Image 5 m x 5 m (b) three-dimensional image (see text for details). The size of image is 

As compared to ordinary microscopes, SPM provides two- and three-dimensional images. The 3D images allow one to see molecules with different diameters (Birdi, 2002a). 

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