TY  - JOUR
AU  - Hansen, Jan
AU  - Pedersen, Jannik N.
AU  - Pedersen, Jan Skov
AU  - Egelhaaf, Stefan U.
AU  - Platten, Florian
TI  - Universal effective interactions of globular proteins close to liquid–liquid phase separation: Corresponding-states behavior reflected in the structure factor
JO  - The journal of chemical physics
VL  - 156
IS  - 24
SN  - 0021-9606
CY  - Melville, NY
PB  - American Institute of Physics
M1  - FZJ-2022-05783
SP  - 244903 -
PY  - 2022
AB  - Intermolecular interactions in protein solutions, in general, contain many contributions. If short-range attractions dominate, the state diagram exhibits liquid–liquid phase separation (LLPS) that is metastable with respect to crystallization. In this case, the extended law of corresponding states (ELCS) suggests that thermodynamic properties are insensitive to details of the underlying interaction potential. Using lysozyme solutions, we investigate the applicability of the ELCS to the static structure factor and how far effective colloidal interaction models can help to rationalize the phase behavior and interactions of protein solutions in the vicinity of the LLPS binodal. The (effective) structure factor has been determined by small-angle x-ray scattering. It can be described by Baxter’s adhesive hard-sphere model, which implies a single fit parameter from which the normalized second virial coefficient b2 is inferred and found to quantitatively agree with previous results from static light scattering. The b2 values are independent of protein concentration but systematically vary with temperature and solution composition, i.e., salt and additive content. If plotted as a function of temperature normalized by the critical temperature, the values of b2 follow a universal behavior. These findings validate the applicability of the ELCS to globular protein solutions and indicate that the ELCS can also be reflected in the structure factor.
LB  - PUB:(DE-HGF)16
C6  - 35778071
UR  - <Go to ISI:>//WOS:000816964600002
DO  - DOI:10.1063/5.0088601
UR  - https://juser.fz-juelich.de/record/915920
ER  -