Protecting biomolecules, such as proteins and enzymes, from the effects of cooling and freezing is important for the storage and handling of pharmaceuticals. Deep eutectic solvents provide a possible alternative biocompatible solvent that will prevent degradation of these delicate molecules. We propose to study the temperature dependent structure of proteins in a variety of deep eutectic solvents. These structural studies will be combined with calorimetric data and SAXS data to understand the mechanism of biomolecular cryoprotection.