Complexation of DNA Block Copolymers with Ionic Liquids
발표자
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초록
내용
Ionic liquids (ILs) are known as designer solvents with low vapor pressure and high ionic and thermal conductivity. Recently, the use of ILs in biological applications has increased due to the availability of non-toxic and biocompatible ILs that can interact with double-stranded DNAs (dsDNAs). Here, we investigate the complexation of ILs with DNA-containing block copolymers to form polyelectrolyte complexes. Double hydrophilic diblock copolymers are first synthesized by coupling poly(ethylene glycol) (PEG) to dsDNA. The resulting dsDNA-b-PEG block copolymers are then complexed with ILs at different charge ratios. The effective binding between the ILs and dsDNA-b-PEG is confirmed by fluorescence binding assay. The morphologies of the complexes are examined by transmission electron microscopy and dynamic light scattering. At sufficiently high IL concentrations, nano-sized polyelectrolyte complexes are observed. We attribute their formation to the electrostatic charge interactions between negatively charged dsDNA blocks and IL cations, which are then further stabilized by the presence of the PEG blocks.