Glass Formation During Room Temperature, Isothermal Drying

Isothermal drying and glass transition of solutions and films have drawn considerable attention from many industries. We here explore the feasibility of modifying the isothermal drying and vitrification kinetics of carbohydrate solutions in order to ensure the stability and quality of their ingredients. Modulated Differential Scanning Calorimetry experiments with isothermally dried trehalose and trehalose/dextran solutions were performed and the glass transition kinetics have been determined. Three distinct drying regimes were observed. With isothermal, isobaric drying at 0%RH, it was indeed possible to reach the glassy state for a trehalose and a trehalosedextran system. With the addition of high molecular weight sugars, the glass transitions of isothermally dried carbohydrate solutions can be accelerated as a function of dextran mass ratio in the sample.