Modeling the protein partitioning in aqueous polymer two-phase systems: influence of polymer concentration and molecular weight

• Published in: Chemical engineering science 2003-07, Vol.58 (13), p.2963-2972
• Main Authors: Lin, Dong-Qiang, Wu, You-Ting, Mei, Le-He, Zhu, Zi-Qiang, Yao, Shan-Jing
• Format: Article
• Language: English
• Subjects: Aqueous two-phase systems; Biological and medical sciences; Biotechnology; Extraction; Fundamental and applied biological sciences. Psychology; Methods. Procedures. Technologies; Modeling; Others; Polymer; Protein partitioning; Thermodynamics process; Various methods and equipments
• ISSN: 0009-2509; 1873-4405
• DOI: 10.1016/S0009-2509(03)00167-2

Aqueous polymer two-phase system provides a powerful method for separation and purification of biomaterials. Among various factors, polymer concentration and polymer molecular weight are essential and have strong impact on the protein partitioning in these systems. Based on the modified Pitzer's model, a simple expression has been obtained for correlating protein partitioning in aqueous polymer two-phase systems with varying polymer concentration and different polymer molecular weights. Using only one group of parameters for each target protein, the partition coefficients of five proteins (lysozyme, chymotrypsinogen-A, bovine serum albumin, transferrin and catalase) in 16 sets of polyethylene glycol (PEG)/dextran systems were correlated. In addition, partition behavior of lactate dehydrogenase in PEG/hydroxypropyl starch systems were measured, correlated and partially predicted. A comparison of calculated and experimental data indicated that the model provides good correlation and prediction abilities on the protein partitioning in aqueous polymer two-phase systems with a wide range of polymer concentration and molecular weight.