Gieseler Henning, Lee Geoffrey
Division of Pharmaceutics, Friedrich-Alexander-University Erlangen, Germany.
Pharm Dev Technol. 2008;13(6):463-72. doi: 10.1080/10837450802309638.
A freeze-drying balance was used to determine momentary drying-rate, m(t), of a sucrose/BSA formulation contained in a vial with varying shelf packing density, Ø2. A comparison between two different laboratory-scale freeze-dryers was made. The effects of Ø2 on m(t) differed between the two units, attributed to drying chamber design and its effects on heat transfer. At high Ø2 the differences are annulled because of the shielding effects of surrounding vials. Parallel effects of Ø2 were also found on product temperature, Tb, measured in the balance vial. Tb was used to calculate vial heat transfer coefficient, Kv. Kv was strongly reduced with increasing Ø2, but reached a plateau value at high Ø2.
使用一台冷冻干燥天平来测定装有不同搁板填充密度（Ø2）的小瓶中蔗糖/牛血清白蛋白制剂的瞬时干燥速率m(t)。对两台不同的实验室规模冷冻干燥机进行了比较。由于干燥室设计及其对热传递的影响，Ø2对m(t)的影响在两台设备之间有所不同。在高Ø2时，由于周围小瓶的屏蔽作用，差异消失。在天平小瓶中测量的产品温度Tb上也发现了Ø2的类似影响。Tb用于计算小瓶传热系数Kv。随着Ø2的增加，Kv大幅降低，但在高Ø2时达到平稳值。
