One of the trends in downstream processing comprises the use of “anything‐but‐chromatography” methods to overcome the current downfalls of standard packed‐bed chromatography. Precipitation and magnetic separation are two techniques already proven to accomplish protein purification from complex media, yet never used in synergy. With the aim to capture antibodies directly from crude extracts, a new approach combining precipitation and magnetic separation is developed and named as affinity magnetic precipitation. A precipitation screening, based on the Hofmeister series, and a commercial precipitation kit are tested with affinity magnetic particles to assess the best condition for antibody capture from human serum plasma and clarified cell supernatant. The best conditions are obtained when using PEG3350 as precipitant at 4 °C for 1 h, reaching 80% purity and 50% recovery of polyclonal antibodies from plasma, and 99% purity with 97% recovery yield of anti‐TNFα mAb from cell supernatants. These results show that the synergetic use of precipitation and magnetic separation can represent an alternative for the efficient capture of antibodies.

中文翻译：

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磁沉淀：蛋白质纯化的新平台。

下游加工的趋势之一包括使用“除色谱法外”的方法来克服当前标准填充床色谱法的下降。沉淀和磁分离是两种已被证明可从复杂介质中纯化蛋白质的技术，但从未用于协同作用。为了直接从粗提物中捕获抗体，开发了一种结合沉淀和磁分离的新方法，并将其称为亲和磁沉淀。对基于Hofmeister系列的沉淀筛选和商用沉淀套件进行了亲和磁性颗粒测试，以评估从人血清血浆和澄清的细胞上清液中捕获抗体的最佳条件。在4°C下使用PEG3350作为沉淀剂1 h时，可获得最佳条件，从血浆中获得80％的纯度和50％的多克隆抗体回收率，从细胞上清液中获得99％的纯度和97％的抗TNFαmAb回收率。这些结果表明，沉淀和磁分离的协同使用可以代表有效捕获抗体的替代方法。