Interfacial partition of plasmid DNA in aqueous two-phase systems

• Main Authors: Luechau, Frank, Ling, Tau Chuan, Lyddiatt, Andrew
• Format: Article
• Language: English
• Published: Elsevier 2009
• Online Access: http://psasir.upm.edu.my/id/eprint/15267/1/Interfacial%20partition%20of%20plasmid%20DNA%20in%20aqueous%20two-phase%20systems.pdf; http://psasir.upm.edu.my/id/eprint/15267/; https://www.sciencedirect.com/science/article/pii/S1383586609001038#!

In this paper, the partition of plasmid DNA (pDNA) in polyethylene glycol (PEG) 300 and di-potassium hydrogen phosphate aqueous two-phase systems (ATPS) under gravity separation was investigated. The influence of temperature (20 and 30 °C) and mode of phase separation (40–60% (w/w) lysate concentrations) on the pDNA partition behaviour was studied. At 20 °C, 70.7% of pDNA partitioned to the top phase while the recoveries in the interface and bottom phase were comparatively small. At 30 °C, the partition had switched from a top phase preference to an interface preference where 73.9% of pDNA was recovered. The distribution of pDNA between the top phase and interface is effectively time-dependent during gravitational phase separation. Systems with lysate concentrations between 40 and 50% (w/w) separated with a continuous bottom phase and a dispersed PEG-rich top phase. For ATPS with 55 and 60% (w/w) lysate, the top phase was continuous and the bottom phase was dispersed.