AEX Buffer Screening Kit

Initial work implementing the DOE was performed using monolith technology due to the high flow rates associated with these columns. After identification of the optimal recipe, however, the formulation was validated across multiple other platforms, including two commonly used AEX resins shown in the figure below.

To ensure the kit is agnostic of the upstream process used (for instance, cell line, media choice, transfection and harvest conditions) and does not affect the ability to successfully utilize the buffer set, multiple processes were implemented and tested using the optimal buffer formulations.

Variations to the downstream processes, such as TFF, affinity, and CEX, may affect the final AEX polishing step. To probe this concern, multiple downstream processes were implemented to verify the applicability of the optimized buffer formulations.

The figure below demonstrates the utility of the kit for various chromatographic modalities. The buffer screening is shown using a linear gradient (left) and then finalized using an isocratic hold (right) to facilitate scale-up requirements.