Capillary gel electrophoresis of nucleic acids in pluronic F127 copolymer liquid crystals

Abstract

The liquid crystalline gel phases of solutions of Pluronic F127, a triblock copolymer, were recently introduced as an alternative to disordered solutions of random coil polymers as replaceable media for capillary gel electrophoresis (CGE). Pluronic F127, from BASF, is a copolymer of poly(ethylene oxide) and poly(propylene oxide) with the approximate formula (EO)106 (PO)70 (EO)106. Polymer chains aggregate into spherical micelles in aqueous solutions, with poly(propylene oxide) chains creating a hydrophobic core surrounded by brushes of hydrated poly(ethylene oxide) tails. Crowding at high concentrations promotes ordering of micelles. Solutions in the range of about 14–24 % polymer are self-supporting, gel-like cubic liquid crystals at 25–30°C, but when cooled they become low viscosity liquids that are easily loaded into capillaries. This article reviews applications of Pluronic F127 media for capillary gel electrophoresis separations of nucleic acids of several types including oligonucleotides, double stranded DNA fragments, and supercoiled plasmid DNAs.