As upstream product titers increase, the downstream chromatographic capture step has become a significant “downstream bottleneck.” Precipitation becomes more attractive under these conditions as the supersaturation driving force increases with the ever‐increasing titer. In this study, two precipitating reagents with orthogonal mechanisms, polyethylene glycol (PEG) as a volume excluder and zinc chloride (ZnCl₂) as a cross linker, were examined as precipitants for two monoclonal antibodies (mAbs), one stable and the other aggregation‐prone, in purified drug substance and harvested cell culture fluid forms. Manual batch solubility and redissolution experiments were performed as scouting experiments. A high throughput (HTP) liquid handling system was used to investigate the design space as fully as possible while reducing time, labor, and material requirements. Precipitation and redissolution were studied by systematically varying the concentrations of PEG and ZnCl₂ to identify combinations that resulted in high yield and good quality for the stable mAb; PEG concentrations in the range 7–7.5 wt/vol% together with 10 mM ZnCl₂ gave a yield of 97% and monomer contents of about 93%. While yield for the unstable mAb was high, quality was not acceptable. Performance at selected conditions was further corroborated for the stable mAb using a continuous tubular precipitation reactor at the laboratory scale. The HTP automation system was a powerful tool for locating desired (customized) conditions for antibodies of different physicochemical properties.

中文翻译：

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通过结合 PEG 和氯化锌沉淀进行抗体纯化的高通量溶解度和再溶解筛选。

随着上游产品滴度的增加，下游的色谱捕获步骤已成为一个重要的“下游瓶颈”。在这些条件下，随着过饱和驱动力随着滴度的不断增加而增加，沉淀变得更具吸引力。在本研究中，两种具有正交机制的沉淀试剂，聚乙二醇 (PEG) 作为体积排除剂和氯化锌 (ZnCl ₂) 作为交联剂，被检测为两种单克隆抗体 (mAb) 的沉淀剂，一种稳定，另一种易于聚集，以纯化的药物物质和收获的细胞培养液形式存在。手动批量溶解度和再溶解实验作为筛选实验进行。使用高通量 (HTP) 液体处理系统尽可能全面地研究设计空间，同时减少时间、劳动力和材料要求。通过系统地改变 PEG 和 ZnCl ₂的浓度来研究沉淀和再溶解，以确定能够获得高产量和高质量稳定 mAb 的组合；PEG 浓度范围为 7–7.5 wt/vol% 以及 10 mM ZnCl ₂产率为97%，单体含量约为93%。虽然不稳定 mAb 的产量很高，但质量不可接受。使用实验室规模的连续管式沉淀反应器进一步证实了稳定 mAb 在选定条件下的性能。HTP 自动化系统是一种强大的工具，用于为不同理化特性的抗体定位所需（定制）条件。