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Independent versus cooperative binding in polyethylenimine-DNA and Poly(L-lysine)-DNA polyplexes.

ABSTRACT: The mechanism of polyethylenimine-DNA and poly(L-lysine)-DNA complex formation at pH 5.2 and 7.4 was studied by a time-resolved spectroscopic method. The formation of a polyplex core was observed to be complete at approximately N/P = 2, at which point nearly all DNA phosphate groups were bound by polymer amine groups. The data were analyzed further both by an independent binding model and by a cooperative model for multivalent ligand binding to multisubunit substrate. At pH 5.2, the polyplex formation was cooperative at all N/P ratios, whereas for pH 7.4 at N/P < 0.6 the polyplex formation followed independent binding changing to cooperative binding at higher N/Ps.

SUBMITTER: Ketola TM

PROVIDER: S-EPMC3888923 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

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Independent versus cooperative binding in polyethylenimine-DNA and Poly(L-lysine)-DNA polyplexes.

Ketola Tiia-Maaria TM Hanzlíková Martina M Leppänen Linda L Raviña Manuela M Bishop Corey J CJ Green Jordan J JJ Urtti Arto A Lemmetyinen Helge H Yliperttula Marjo M Vuorimaa-Laukkanen Elina E

The journal of physical chemistry. B 20130828 36

The mechanism of polyethylenimine-DNA and poly(L-lysine)-DNA complex formation at pH 5.2 and 7.4 was studied by a time-resolved spectroscopic method. The formation of a polyplex core was observed to be complete at approximately N/P = 2, at which point nearly all DNA phosphate groups were bound by polymer amine groups. The data were analyzed further both by an independent binding model and by a cooperative model for multivalent ligand binding to multisubunit substrate. At pH 5.2, the polyplex for ...[more]

PMID: 23941196

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