The Influence of Inorganic Salts on the Phase Diagram and Separating Ability of Aqueous Biphasic System: Peg/Sodium Citrate-Water

The purpose of the proposed research is to ensure that the value of the distinction is adjusted to each application by using various supplements to separate and clean up biological objects. The work presents the results of studies of the phase diagram of the biphasic system composed of polyethylene glycol (PEG)/sodium citrate-water and the effect of inorganic salts (sodium sulfate, sodium carbonate, sodium nitrate, potassium sulfate, potassium chloride, potassium iodide, potassium bromide) on the separating ability of this biphasic system. Analysis of the data presented shows that the change in the parameters of the phase diagram and different values of the separating ability (for PEG—sodium citrate-water system n* = 9.3) of the biphasic system, depends on the nature of the additives. The utilized inorganic salts change the structure of water clusters. Following the change, the biphasic system component relative hydrophobicity rises, which results in phase separation. The displacements of the binodal of the phase diagram in the direction of the origin of coordinates, an increase in the area of the heterogeneous region of the diagram upon the introduction of the studied salts indicate that these salts have a structuring effect on the aqueous medium.