Continuous aqueous two-phase systems devices for the recovery of biological products

•Critical review on selected devices employed for ATPS continuous processing is presented.•Operational and design parameters that have an impact upon system performance are reviewed.•Current trends and challenges in the implementation of continuous ATPS approaches are discussed.

Aqueous two-phase systems (ATPS) have proved to be a suitable technique for the recovery of biological products. Although ATPS have been in the field of primary recovery and purification of products for several years, the majority of the studies exploiting ATPS are usually based on batch mode operation. Reports on the potential of using continuous ATPS are not common. This review attempts to present a practical analysis of selected devices employed for ATPS continuous processing, from the conventional column contactors to novel designed mixer-settler units. A critical analysis of operational and design parameters that impact the system performance is presented. Current trends on the implementation of continuous ATPS approaches are discussed, together with the major challenges faced for the generic adoption of the technique. Conclusions are drawn on the major contribution of previous studies in the field to provide a better understanding of the technique for the newcomers.