Application of Aqueous Two-Phase Systems in the Extraction of Bovine Serum Albumin

Abstract

Protein partitioning in an Aqueous Two-Phase System (ATPS) has been found to be a powerful method for extracting and separating mixtures of biomolecules. In Aqueous Two-Phase Systems, many factors influence the Partition coefficient (K) (which is the ratio of protein concentration in the top phase to that in the bottom phase) and the Recovery percent (Rec%). Two systems of ATPS were used: first, polyethylene glycol (PEG4000)/sodium phosphate (SPH), and second, PEG4000/Dextran. The behavior of Rec% and (K) of pure Bovine Serum Albumin (BSA) in (ATPS) has been investigated throughout the study of the effects of five parameters: (temperature (T), the concentration of polyethylene glycol (PEG4000), the concentration of sodium phosphate or Dextran, pH, and the addition of sodium chloride as a supporting agent). In both systems, pH was the more significant parameter on a Recovery percent (Rec%) and partition coefficient (K). In the first system, the maximum (Rec%) and (K) was 98.08% and 50.99, respectively, at a temperature of 31°C, the concentration of PEG4000 of 1.5 g/10 ml, the concentration of sodium phosphate at 2.4 g/10 ml, pH 10, and the concentration of NaCl at 0.5 M. While in the second system, the parameter that has a more significant effect on (Rec%) and (K) was the temperature. The maximum (Rec%) and (K) were 97.54% and 39.7 respectively at a temperature of 31°C, with a concentration of PEG4000 1.5 g/10 ml, the concentration of Dextran 2.4 g/10 ml, pH 5, and concentration of NaCl at 0.1 M.