Stability of DNA-containing interpolyelectrolyte complexes in water-salt solutions

✍ Scribed by Vladimir A. Izumrudov; Marina V. Zhiryakova

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 110 KB
• Volume: 200
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/(sici)1521-3935(19991101)200:11<2533::aid-macp2533>3.0.co;2-r

✦ Synopsis

Destruction of interpolyelectrolyte complexes (PEC) formed by DNA and different poly(Nalkyl-4-vinylpyridinium) cations was achieved by addition of low molecular weight electrolytes. Monitoring of PEC dissociation was carried out by fluorescence quenching using the ability of the cationic dye ethidium bromide to intercalate into free sites of the DNA double helix accompanied by fluorescence. Degree of polymerization and charge density of the polycations as well as their N-alkyl substituentes (alkyl = methyl, ethyl, and propyl) were shown to be factors influencing the stability of PEC. The ability of added cations and anions to dissociate PEC decreases in the order Ca ++ A