冻干保护剂溶液低温退火特性的研究

利用差示扫描量热仪(DSC)研究了10%叔丁醇/10%蔗糖/水溶液的冻结特性, 退火温度及退火时间, 分析了溶液的退火行为. 实验结果表明, 溶液降温时, 蔗糖的存在阻碍了叔丁醇析出, 最大冻结浓缩溶液玻璃化转变温度Tg′由－32.5 ℃降低到－42.0 ℃, 升温时在－30 ℃叔丁醇发生反玻璃化. 在反玻璃化峰附近的温度进行退火可使叔丁醇充分析出, Tg′由－42.0 ℃上升到－34.9 ℃. 所需的退火时间与退火温度有关, 退火温度越接近Tg′, 所需的退火时间越长. 在－37 ℃时, 退火20 min可完全消除反玻璃化.

Annealing Properties of Lyoprotectant Solution

In order to examine the annealing behaviors of aqueous solutions of 10% tertiary butyl alcohol (TBA) and 10% sucrose in freeze- drying, a differential scanning calorimeter (DSC) has been employed to study freezing properties, annealing temperature, and annealing time. The experimental results show that when the solution is cooled, the existence of sucrose hinders the crystallization of TBA and the value of Tg′ decreases from －32.5 ℃ to －42.0 ℃, and TBA devitrifies at －30 ℃ when the solution is heated. When annealed at different temperatures around the devitrification peak, TBA all can crystallize completely and the value of Tg′ increases from －42.0 ℃ to －34.9 ℃. Annealing time depends on annealing temperature. The closer the annealing temperature is to Tg′, the longer the annealing time is. The devitrification will disappear after annealing at －37 ℃ for 20 min.