Microscopic and spectroscopic analysis of chitosan-DNA conjugates

D Agudelo; L Kreplak; H A Tajmir-Riahi

doi:10.1016/j.carbpol.2015.09.080

Microscopic and spectroscopic analysis of chitosan-DNA conjugates

Carbohydr Polym. 2016 Feb 10:137:207-213. doi: 10.1016/j.carbpol.2015.09.080. Epub 2015 Oct 22.

Authors

D Agudelo¹, L Kreplak², H A Tajmir-Riahi³

Affiliations

¹ Department of Chemistry-Biochemistry and Physics, Université of Québec at Trois-Rivières, C.P. 500, Trois-Rivières, Québec, Canada G9A 5H7.
² Department of Physics and Atmospheric Science, Sir James Dunn Building, Dalhousie, University, Lord Dalhousie Drive, Halifax, NS, Canada B3H 4R2.
³ Department of Chemistry-Biochemistry and Physics, Université of Québec at Trois-Rivières, C.P. 500, Trois-Rivières, Québec, Canada G9A 5H7. Electronic address: tajmirri@uqtr.ca.

PMID: 26686122
DOI: 10.1016/j.carbpol.2015.09.080

Abstract

Conjugations of DNA with chitosans 15 kD (ch-15), 100 kD (ch-100) and 200 kD (ch-200) were investigated in aqueous solution at pH 5.5-6.5. Multiple spectroscopic methods and atomic force microscopy (AFM) were used to locate the chitosan binding sites and the effect of polymer conjugation on DNA compaction and particle formation. Structural analysis showed that chitosan-DNA conjugation is mainly via electrostatic interactions through polymer cationic charged NH2 and negatively charged backbone phosphate groups. As polymer size increases major DNA compaction and particle formation occurs. At high chitosan concentration major DNA structural changes observed indicating a partial B to A-DNA conformational transition.

Keywords: AFM; Binding; Chitosan; Conformation; DNA; Morphology.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Chitosan / chemistry*
DNA / chemistry*
Microscopy, Atomic Force
Molecular Conformation

Substances

DNA
Chitosan