Integration of a complete downstream process for the automated lab-scale production of a recombinant protein.

In this work, an automated downstream process for the purification and formulation of a recombinant protein was integrated at lab scale in a single chromatography unit. The purification chain consists of three bind-and-elute chromatography columns, a flow-through membrane chromatography step, and a final ultrafiltration-diafiltration (UFDF) step to concentrate and formulate the sample. An integrated downstream process increases productivity and decreases process time and hold-up volume. In addition, the automation of the process allows reducing the manual work and increases reproducibility. To integrate the downstream steps, all the intermediate tanks are removed, and the eluate of a column is loaded directly onto the next one. This makes it necessary to design the process in order to minimize the column volumes and the process time. A research software called Orbit was used to automate the purification process and implement a UFDF step in the chromatography unit. The whole downstream sequence was successfully implemented at lab scale, getting a pure concentrated and formulated product with a productivity of 1.09 mg mL-1 h-1, achieving a time reduction from almost two to one working day, while getting a similar yield and purity. Regarding the UFDF operation, the sample was concentrated 10 times, and 97% of the old buffer was exchanged by the formulation buffer with a sequential diafiltration.