HIGH-RESOLUTION ATOMIC-FORCE MICROSCOPY OF DEXTRAN MONOLAYER HYDRATION

Atomic force microscopy has been employed for the in situ investigatio n of the molecular hydration of thiolated dextran monolayers within a liquid environment. The studies have demonstrated the ability to measu re corresponding changes in both monolayer morphology and elasticity d ue to the hydration state of dextran. Imaging in water allows the visu alization of macromolecular swelling, matched by an increase in surfac e elasticity monitored via the analysis of force-distance curves. Subs equent imaging in a propanol environment leads to dehydration effects observed through a relaxation of swelling and a decrease in surface el asticity.