Selection and Use of Poly Ethylene Glycol and Phosphate Based Aqueous Two-Phase Systems for the Separation of Proteins by Centrifugal Partition Chromatography

Abstract

For an efficient separation with centrifugal partition chromatography (CPC) the selection of suitable biphasic phase systems is of crucial importance. Commonly, aqueous-organic systems have been widely used for the separation of natural products. Thus, a lot of knowledge about the selection of suitable systems and appropriate operation conditions of CPC is available. Alternatively, aqueous two-phase systems (ATPS) can be used in CPC. These systems offer the possibility to purify biotechnological substances like proteins. However, the selection and use of ATPS in CPC and accordingly the selection of appropriate operation conditions have rarely been investigated. In order to improve the knowledge, the focus of this research is on the selection of suitable ATPS and operation conditions for an efficient separation of biomolecules in CPC. Several systems, based on polyethylene glycol and phosphate salts have found to be suitable for use in CPC. Thereby, the hydrodynamic in the chamber is of major importance because it determines the stability and the performance during the separation run. An additional important aspect within the ATPS selection is the possibility to adjust the partition coefficient of the target compounds. This was achieved by changing the pH value of the system. Both aspects, hydrodynamic and adjustment of the partition coefficients were investigated in this study and the results obtained will help to select suitable ATPS and operating conditions for CPC separation of biomolecules.