Application of integral‐equation theory to aqueous two‐phase partitioning systems

Contribution of protein charge to partitioning in aqueous two-phase systems

“…Superscripts T and B denote top phase and bottom phase, respectively. Different models have been developed for i chem and thus account for the non-electrostatic interactions, i.e., the ln ⌫ i B /⌫ i T term in Equation (5) (Baskir et al, 1987(Baskir et al, , 1989Brooks et al, 1985;Haynes et al, 1991Haynes et al, , 1993King et al, 1988). The Flory-Huggins model (a lattice model) and the osmotic virial expansion model are among the most important.…”

“…The required second virial coefficients can also be measured by multi-angle laser light scattering (Haynes et al, 1989(Haynes et al, , 1991(Haynes et al, , 1993King et al, 1988;Kratochvil, 1987;Rathbone et al, 1990). Comparing the value of a regressed from Equation (14) to the value determined from light scattering will provide insight as to how different molecular interactions influence the protein partitioning behavior in an aqueous two-phase system.…”

“…Comparing the value of a regressed from Equation (14) to the value determined from light scattering will provide insight as to how different molecular interactions influence the protein partitioning behavior in an aqueous two-phase system. More recently, the phaseequilibrium calculations based on virial coefficients have been directly linked to specific intermolecular interactions of the components (Haynes et al, 1993;Gaube et al, 1993;Coen et al, 1995). Such a step requires a larger number of molecular properties not readily available for different phase systems and proteins.…”

“…Considerable advances in the theory of aqueous twophase systems and partitioning phenomena have been made in the last ten years (Abbot et al, 1990;Albertsson, 1986;Baskir et al, 1987Baskir et al, , 1989Hsu, 1989, 1990;Eiteman et al, 1994;Forciniti and Hall, 1990;Forciniti et al, 1991Forciniti et al, , 1992Franco et al, 1996a, b;Gro␤mann et al, 1995;Hartounian et al, 1994;Haynes et al, 1989Haynes et al, , 1991Haynes et al, , 1993King et al 1988;Peng et al, 1995;Walter et al, 1985Walter et al, , 1991Zaslavsky, 1995). Interactions determining protein partitioning in phase systems have been characterized (Albertsson, 1986).…”

Solubility of Amino Acids, Sugars, and Proteins

“…The electrical potential difference between the aqueous phases is attributed to the unevenly distribution of the ionic species and seems to play an important role in the partition of proteins in ATPSs [73,74]. Despite the predominant influence of the electrical contribution on the partition of charged proteins, some doubt remains about the experimental assessment as well as about the theoretical explanation of the electrical potential difference between phases (see, e.g., [73]).…”