Document Detail


DNA and cationic surfactant complexes at hydrophilic surfaces. An ellipsometry and surface force study.
MedLine Citation:
PMID:  15379480     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The adsorption and formation of DNA and cationic surfactant complexes at the silica-aqueous interface have been studied by ellipsometry. The interaction between the DNA-surfactant complexes at the mica-aqueous interface has been determined by the interferometric surface force apparatus. Adsorption was as expected not observed on negatively charged hydrophilic surfaces for DNA and when DNA-cationic surfactant complexes were negatively charged. However, adsorption was observed when there is an excess of cationic surfactant, just below the point of phase separation. The adsorption process requires hours to reach steady state. The adsorbed layer thickness is large at low surface coverage but becomes more compact and thinner at high coverage. A long-range repulsive force was observed between adsorbed layers of DNA-cationic surfactant complexes, which was suggested to be of both electrostatic and steric origin. The forces were found to be dependent on the equilibration time and the experimental pathway.
Authors:
Marité Cárdenas; José Campos-Terán; Tommy Nylander; Björn Lindman
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Langmuir : the ACS journal of surfaces and colloids     Volume:  20     ISSN:  0743-7463     ISO Abbreviation:  Langmuir     Publication Date:  2004 Sep 
Date Detail:
Created Date:  2004-09-21     Completed Date:  2006-08-21     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  9882736     Medline TA:  Langmuir     Country:  United States    
Other Details:
Languages:  eng     Pagination:  8597-603     Citation Subset:  IM    
Affiliation:
Center for Chemistry and Chemical Engineering, Physical Chemistry 1, University of Lund, PO Box 124, SE-221 00, Sweden. marite.cardenas@fkem1.lu.se
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MeSH Terms
Descriptor/Qualifier:
Adsorption
Aluminum Silicates / chemistry
Cations / chemistry
DNA / chemistry*,  metabolism
Macromolecular Substances / chemistry*
Surface Properties
Surface-Active Agents / chemistry*,  metabolism
Water / chemistry
Chemical
Reg. No./Substance:
0/Aluminum Silicates; 0/Cations; 0/Macromolecular Substances; 0/Surface-Active Agents; 12001-26-2/mica; 7732-18-5/Water; 9007-49-2/DNA

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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