Study of DNA Separation in Aqueous-Salt Two-Phase System

Plasmid DNA (pDNA) based gene therapy belongs to the category of non-viral systems. Generally, their production is considered more scalable, the process is easier to control, monitor and quality control testing is considered easier than that for viral vectors. Since downstream processing techniques for the recovery of nanobioparticles face to problems other than those encountered during the recovery of biomolecules such as peptides and proteins, thus downstream process routes that are currently in use for bioparticles have to be re-designed for such nanoparticles. Aqueous two phase system (ATPS) is one of the processes that are used for this purpose. Partitioning of plasmid DNA in ATPS has been shown to provide a powerful method for separation and purification mixture of nanobioparticles. In this paper, Polymer-salt system have been studying and the partition behavior of pDNA in aqueous two phase systems of polyethylene glycol 300 – potassium phosphate at different temperatures and lysate concentrations were investigated. The volume ratio and recovery of pDNA in top, bottom and interface were measured. The results showed that lysate concentration from 10 to 50 mg/ml as well as temperature from 5 to 45 C have a significant effect on pDNA recovery.