title: Polyelectrolyte complexes as a tool for purification of plasmid DNA. Background and development.
abstract: The demand for highly purified plasmids in gene therapy and plasmid-based vaccines requires large-scale production of pharmaceutical-grade plasmid. Plasmid DNA was selectively precipitated from a clarified alkaline lysate using the polycation poly(N,N'-dimethyldiallylammonium) chloride which formed insoluble polyelectrolyte complex (PEC) with the plasmid DNA. Soluble PECs of DNA with polycations have earlier been used for cell transformation, but now the focus has been on insoluble PECs. Both DNA and RNA form stable PECs with synthetic polycations. However, it was possible to find a range of salt concentration where plasmid DNA was quantitatively precipitated whereas RNA remained in solution. The precipitated plasmid DNA was resolubilised at high salt concentration and the polycation was removed by gel-filtration.
authors.affiliation: Department of Biotechnology, Center for Chemistry and Chemical Engineering, Lund University, PO Box 124, S-221 00 Lund, Sweden.
authors.forename: Per-Olof
authors.initials: PO
authors.lastname: Wahlund
authors.forename: Per-Erik
authors.initials: PE
authors.lastname: Gustavsson
authors.forename: Vladimir A
authors.initials: VA
authors.lastname: Izumrudov
authors.forename: Per-Olof
authors.initials: PO
authors.lastname: Larsson
authors.forename: Igor Yu
authors.initials: IY
authors.lastname: Galaev
mesh_terms: D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D004247:DNA / Q000737:chemistry / Q000302:isolation & purification*; D004573:Electrolytes / Q000737:chemistry*; D004587:Electrophoresis, Agar Gel; D004591:Electrophoresis, Polyacrylamide Gel; D010957:Plasmids / Q000302:isolation & purification*
chemical_list: D004573:Electrolytes; D004247:DNA