Experimental simulation of macromolecules in trehalose aqueous solutions: A photon correlation spectroscopy study

The protective effect of trehalose on biological membranes against freezing or dehydration has been the subject of many studies aimed to understand th e reasons why some lower organisms, under stress conditions, synthesize tre halose. In this work we report the results of a study on Poly(Ethylene Oxid e)/trehalose/water mixtures performed by Photon Correlation Spectroscopy. T he chemical structure of the polymer, simpler than that of proteins and its helical conformation in water, constitute a useful starting point for unde rstanding the more complex protein/trehalose/water interactions. In order t o distinguish the different dynamics, trehalose and PEO have been studied s eparately in water, at different concentration and temperature values; then the ternary PEO/trehalose/water system has been investigated at different sugar amounts. The obtained findings support the "water-replacement" hypoth esis, indicating that a direct polymer-trehalose interaction occurs. Furthe rmore, trehalose is shown to affect the swelling properties of the polymer with temperature, stabilizing its conformation. (C) 1999 American Institute of Physics. [S0021-9606(99)50742-3].