Abstract
Freezing of aqueous solutions concentrates solutes into highly viscose phases surrounding ice crystals. Various solutes have different tendencies to crystallize or remain amorphous in the frozen solutions. Thermal analysis of the frozen solutions shows highest critical product temperatures (Tg', Tc, Teu) required to retain the products from physical collapse or melt-back phenomena during the primary drying process. Hydrogen-bondings and electrostatic interactions between multiple solutes affect the eutectic crystallization and the transition temperatures of frozen solutions. Application of the thermal analysis to formulation and process design of freeze-dried pharmaceuticals was discussed.
https://ror.org/04s629c33 
