Lyophilization of cosolvent systems may be a beneficial way of enhancing both physical and chemical stability of a drug product. The objective of this research is to establish whether cosolvent systems commonly used in the formulation of poorly water-soluble drugs can be successfully lyophilized. Polyethylene glycol (PEG) 400 was selected because it is widely used and can be easily frozen. The addition of PEG 400 to commonly used bulking agents, such as mannitol, sucrose, or polyvinylpyrrolidone, caused a significant change in the thermal properties of the bulking agents as observed by modulated differential scanning calorimetry. In addition, PEG 8000 was evaluated as a bulking agent because it also can function as a cosolvent in solution and forms an acceptable cake after lyophilization. Addition of PEG 400 to PEG 8000 caused negligible changes in the thermogram of this bulking agent. Surprisingly, the combination of PEG 8000 and PEG 400 forms a solid lyophilized cake. The current system can be best described as the lyophilization of a miscible solution of PEG 8000 and PEG 400 resulting in a lyophile that has a crystalline structure of PEG 8000 which is able to support PEG 400.

中文翻译：

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聚乙二醇混合物的冻干。

助溶剂系统的冻干可能是增强药物产品的物理和化学稳定性的有益方法。这项研究的目的是确定水溶性差的药物配方中常用的助溶剂系统是否可以成功冻干。选择聚乙二醇（PEG）400是因为它被广泛使用并且易于冷冻。如通过调制差示扫描量热法所观察到的，将PEG 400添加到常用的增量剂例如甘露醇，蔗糖或聚乙烯吡咯烷酮中，引起了增量剂的热性质的显着变化。另外，由于PEG 8000还可以作为溶液中的助溶剂并在冻干后形成可接受的滤饼，因此被评估为填充剂。在PEG 8000中添加PEG 400导致该填充剂的热分析图变化可忽略不计。令人惊讶地，PEG 8000和PEG 400的组合形成固体冻干饼。最好将当前系统描述为PEG 8000和PEG 400的可混溶溶液的冻干，从而产生具有PEG 8000晶体结构且能够支持PEG 400的冻干物。