Freeze Drying of Pharmaceuticals. On the Change in the Macroscopic Appearance during Freezing and the Critical Temperature necessary for Freeze Drying

摘要: The low temperature behavior of solutions simple substances and pharmaceuticals was studied. authors found noticeable changes in the macroscopic appearance during freezing some which exhibited eutectic behavior. Appearance were classified into four types : I) no change, II) slight increase opacity, III) very formation clear white spots due to crystallization with slow rate growth spots, IV) high growth. temperatures (Te) obtained from at faded or disappeared. collapsing (Tc) also observation freeze drying, above frozen layer solution became puffed collapsed. electrical resistances specimens measured cooling rewarming. These data compared each other discuss meaning drying as follows. crowds crystal structures. Tc observed Te for behavior, froze solid but supercooled super-eutectic states supposed be lost solidity.