English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/9525
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL | DATACITE
Exportar a otros formatos:


Compaction process of calf thymus DNA by mixed cationic-zwitterionic liposomes: a physicochemical study

AuthorsRodríguez-Pulido, Alberto; Aicart, Emilio; Llorca, Óscar ; Junquera, Elena
Issue Date21-Feb-2008
PublisherAmerican Chemical Society
CitationJ. Phys. Chem. B 112 (7): 2187-2197 (2008)
AbstractThe compaction of calf thymus DNA (CT-DNA) by cationic liposomes constituted by a 1:1 mixture of a cationic lipid, 1,2-distearoyl-3-(trimethylammonio)propane chloride (DSTAP), and a zwitterionic lipid, 1,2-dioleoyl-sn-glycero-3-phosphatidylethanolamine (DOPE, null net charge at pH = 7.4), has been evaluated in aqueous buffered solution at 298.15 K by means of conductometry, electrophoretic mobility, cryo-TEM, and fluorescence spectroscopy techniques. The results reveal that DSTAP/DOPE liposomes are mostly spherical and unilamelar, with a mean diameter of around 77 ± 20 nm and a positively charged surface with a charge density of σ(ζ) = (21 ± 1) × 10-3 C m-2. When CT-DNA is present, the genosomes DSTAP/DOPE/CT-DNA, formed by means of a surface electrostatic interaction, are generally smaller than the liposomes. Furthermore, they show a tendency to fuse forming cluster-type structures when approaching isoneutrality, which has been determined by the electrochemical methods at around (L/D)(Φ) = 5.6. The analysis of the decrease on the fluorescence emission of the fluorophore ethidium bromide, EtBr, initially intercalated between DNA base pairs, as long as the genosomes are formed has permitted us to confirm the electrostatic character of the DNA−liposome interaction.
Description11 pages, 10 figures.-- PMID: 18220388 [PubMed].-- Supporting Information (Emission fluorescence spectra of EtBr in the presence of DSTAP/DOPE liposomes at different L/D ratios, 3 pages) available at: http://pubs.acs.org/doi/suppl/10.1021/jp7095828/suppl_file/jp7095828-file003.pdf
Publisher version (URL)http://dx.doi.org/10.1021/jp7095828
Appears in Collections:(CIB) Artículos
Files in This Item:
File Description SizeFormat 
Acceso restringido.pdf21,67 kBAdobe PDFThumbnail
Show full item record
Review this work

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.