Abstract
The interactions between DNAs and cationic comb-type copolymers like those with quaternary ammonium with N-methylated groups have applications in nanotechnology. N-methylated poly(L-lysine)-graft-dextran copolymers (MPLL-g-Dex) were obtained by methylation of poly(L-lysine)-graft-dextran copolymers (PLL-g-Dex) using dimethyl sulfate under weak basic conditions. The resulting copolymers were characterized using NMR spectroscopy and gel permeation chromatography-multiangle light scattering (GPC-MALS). Both primary and secondary amino groups of the PLL backbones were thoroughly methylated to form quaternary ammonium groups without fragmentation of PLL-g-Dex chains or other detectable side reactions. The interactions of the copolymers with DNAs were assessed by UV melting curves and fluorescence correlation spectroscopic measurements. PLL-g-Dex interacts with double-stranded DNA (dsDNA) in a sequence-independent manner. In contrast the MPLL-g-Dex affinity was lower for dsDNA with higher GC content than for DNA with low GC content. The results suggest that MPLL-g-Dex interacts with DNAs not only through ionic interactions, but also by hydrophobic interactions.
Original language | English |
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Pages (from-to) | 979-983 |
Number of pages | 5 |
Journal | Current Nanoscience |
Volume | 7 |
Issue number | 6 |
DOIs | |
Publication status | Published - Dec 2011 |
All Science Journal Classification (ASJC) codes
- Biotechnology
- Bioengineering
- Medicine (miscellaneous)
- Biomedical Engineering
- Pharmaceutical Science