Thermal Stabilizing Effect of Amorphous Matrices of Sugars on Freeze-dried Proteins

Thermal stabilizing effect of sugars on freeze-dried proteins is studied remarking the reaction between the stabilizing effect and the degree of crystallinity of sugars. It is found that thermal stabilizing effect is higher when sugar is amorphous than crystalline. This thermal stabilizing effect is closely related to hydrogen bond between sugar molecules and proteins. It is also found that except the case of low moisture content protein can stabilize amorphous matrix of sugar and prevent its crystallization. Thus, we can deduce that sugars and proteins work together to maintain protein activities.