Imaging structured water and bound polysaccharide on mica surface at ambient temperature.

The presence of a water layer on the surface of muscovite mica under ambient conditions is well established. The water molecules are well ordered and seem to be oriented, leading to an icelike monolayer (probably ferroelectric) in epitaxial relation with the mica surface. We have imaged and characterized the height and contact angle of ordered water layer(s) formed by wetting and de-wetting processes on mica surfaces at different states of hydration by tapping mode atomic force microscopy. Implications that the presence of such an ordered water layer may have for imaging of biological samples are also discussed, with consideration of data for the polysaccharide hyaluronan.