Thermoseparating water/polymer system: a novel one-polymer aqueous two-phase system for protein purification.

摘要: In this study we show that proteins can be partitioned and separated in a novel aqueous two-phase system composed of only one polymer water solution. This represents an attractive alternative to traditional systems which uses either two polymers (e.g., PEG/dextran) or high-salt concentration PEG/salt). The the new is linear random copolymer ethylene oxide propylene groups has been hydrophobically modified with myristyl (C14H29) at both ends (HM-EOPO). thermoseparates water, cloud point 14degreesC. HM-EOPO forms top phase almost 100% bottom 5-9% when 17-30degreesC. self-associating micellar-like structures CMC 12 µM (0.01%). partitioning behavior three (lysozyme, bovine serum albumin, apolipoprotein A-1) water/HM-EOPO studied, as well effect various ions, pH, temperature on protein partitioning. amphiphilic A-1 was strongly HM-EOPO-rich within broad-temperature range. hydrophobic directed addition salt. Below isoelectric (pI) BSA above pI NaClO4was added system. Lysozyme NaClO4, Na-phosphate. possibility direct between phases shows used for separations. tested purification from human plasma Escherichia coli extract. Apolipoprotein could recovered majority contaminating phase. By adding water/buffer higher pH 100 mM raising separation, back-extracted into strong potential use biotechnical extractions it operated moderate temperatures salt concentrations furthermore, recovered. © 1999 John Wiley & Sons, Inc. Biotechnol Bioeng 66: 247-257, 1999. (Less)