447293 Hybrid Shortcut-Modell for Estimating Partition Coefficients in Aqueous Two-Phase Extraction of Therapeutic Proteins
One promising and fast measure accounting for complex interactions of biological macromolecules is the second osmotic virial coefficient (B22) characterizing the interactions between the biological macromolecules in solution and the cross virial coefficient (B23) characterizing interactions of the biological macromolecules with the salts / impurities. It combines the different influence factors such as pH, Temperature, solvent, salt and salt concentration within one measure.
B22 as well as B23 data was measured using composition gradient multi angle light scattering (GC-MALS) for different proteins and salts in aqueous solution. The results were then used to characterize the distribution behavior of the target protein in the ATPS dependent on the displacement salt. The results point to the fact, that based on B22 and B23 the suitability of a salt as displacer for proteins in aqueous two-phase systems can be investigated. One major advantage using this approach is the fact, that the partition coefficient can be estimated using a hybrid ShortCut Modell based on a minimal set of experimental data. Furthermore the influence of the displacer (salt) on the solubility of the protein can be judged qualitatively serving as an ideal first measure in the development of aqueous two-phase extraction systems. The results will help to improve the development and optimization of ATPS used for efficient separation of processes.