| Abstract
| - Synthesis of β-D-Gal-(1 → 3)-β-D-GalNAc coupled to HOC2H4NHCOC15H30SH is described. This compoundwas coadsorbed at various proportions with C2H5OC2H4NHCOC15H30SH to form statistically mixed self-assembled monolayers (SAMs) on gold in an attempt to mimic the properties of the active domain in antifreezeglycoproteins (AFGPs). The monolayers were characterized by null ellipsometry, contact angle goniometry,X-ray photoelectron spectroscopy, and infrared reflection−absorption spectroscopy. The disaccharide compoundadsorbed preferentially, and SAMs prepared at a solution molar ratio >0.3 displayed total wetting. The mixedSAMs showed well-organized alkyl chains up to a disaccharide surface fraction of 0.8. The amount of gaucheconformers in the alkyls increased rapidly above this point, and the monolayers became disordered and lessdensely packed. Furthermore, the generated mixed SAMs were subjected to water vapor at constant relativehumidity and the subsequent ice crystallization on a cooled substrate was monitored via an optical microscope.Interestingly, rapid crystallization occurred within a narrow range of temperatures on mixed SAMs with ahigh disaccharide content, surface fraction >0.3. The reported crystallization temperatures and the ice layertopography were compared with results obtained for a much simpler reference system composed of −OH/−CH3 terminated n-alkanethiols in order to account for changes in topography of the water/ice layer withsurface energy. Although preliminary, the obtained results can be useful in the search for the molecularmechanism behind the antifreeze activity of AFGPs.
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