This work reported the application of a twin-column recycling chromatography system for the separation of three minor impurities in crude aloe-emodin. The whole process went through three steps, each using a different mobile phase to separate corresponding impurity, which were integrated and automatically operated in a single device. Despite these impurities peaked closely in high-performance liquid chromatography, they were successfully purified to a content exceeding 97%. In addition, the lab-scale separation could reach the yields at the mg-level. The high efficacy should be mainly attributed to the introduction of a small step solvent gradient between the upstream and downstream columns, which helped to counterbalance the band broadening. This report suggested that such an automated chromatographic system could provide fast and accurate separation of multiple impurities, allow the process of high-throughput samples, and reduce the time required for purification and recovery of minor impurities in drugs.

中文翻译：

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循环色谱法分离纯化原料药中杂质的三步一体化工艺


这项工作报告了应用双柱回收色谱系统分离粗芦荟大黄素中的三种微量杂质。整个过程经历三个步骤，每个步骤使用不同的流动相分离相应的杂质，并在单个设备中集成并自动操作。尽管这些杂质在高效液相色谱中峰值接近，但它们被成功纯化至含量超过 97%。此外，实验室规模的分离可以达到毫克级的产率。高效率主要归因于在上游和下游柱之间引入小步溶剂梯度，这有助于平衡谱带展宽。该报告表明，这种自动化色谱系统可以快速准确地分离多种杂质，允许处理高通量样品，并减少纯化和回收药物中微量杂质所需的时间。