Method for purifying bispecific antibody by cation exchange chromatography

The invention relates to a method for purifying a bispecific antibody by cation exchange chromatography. The method comprises the following steps: loading a bispecific antibody solution to a cation exchange chromatography column under the loading conditions that the pH is 4.0-7.0 and the conductivity is 3-17mS/cm by adopting an overload mode that the overload multiple is 3-15 times of the dynamic binding capacity, balancing the column by adopting an equilibrium buffer solution with the pH and the conductivity respectively the same as those of the loading conditions, and collecting the flow-through liquid. The method has the advantages of high purification purity, high recovery rate, filler saving and labor hour saving. 本发明涉及一种采用阳离子交换层析法纯化双特异性抗体的方法。所述方法包括：采用过载倍数为动态结合载量的3-15倍的过载模式，在pH为4.0-7.0，电导率为3-17mS/cm的上样条件下将双特异性抗体溶液上样至阳离子交换层析柱，采用pH以及电导率分别与前述上样条件的pH以及电导率相同的平衡缓冲液平衡柱子，收集流穿液。所述方法具有提纯纯度高，回收率高，节约填料和工时的优点。