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Cationic agents for DNA compaction
Gaweda, Sylwia; Morán, M. Carmen; Pais, Alberto A. C. C.; Dias, Rita S.; Schillén, Karin; Lindman, Björn; Miguel, M. GraçaFluorescence microscopy was used to investigate the conformational changes of individual T4 DNA molecules induced by different compacting agents, namely the cationic surfactants, cetyltrimethylammonium bromide (CTAB) and chloride (CTAC), iron(III), lysozyme, and protamine sulfate. A protocol for establishing size estimates is suggested to obtain reproducible results. Observations show that in the presence of ly...
Effect of the Head-Group Geometry of Amino Acid-Based Cationic Surfactants on I...
Jadhav, Vaibhav; Maiti, Souvik; Dasgupta, Antara; Das, Prasanta Kumar; Dias, Rita S.; Miguel, Maria G.; Lindman, BjörnThe interaction between DNA and different types of amino acid-based cationic surfactants was investigated. Particular attention was directed to determine the extent of influence of surfactant head-group geometry toward tuning the interaction behavior of these surfactants with DNA. An overview is obtained by gel retardation assay, isothermal titration calorimetry, fluorescence spectroscopy, and circular dichrois...
Interaction between DNA and Cationic Surfactants: Effect of DNA Conformation an...
Dias, Rita S.; Magno, Luís M.; Valente, Artur J. M.; Das, Dibyendu; Das, Prasanta K.; Maiti, Souvik; Miguel, Maria G.; Lindman, BjörnThe interactions between DNA and a number of different cationic surfactants, differing in headgroup polarity, were investigated by electric conductivity measurements and fluorescence microscopy. It was observed that, the critical association concentration (cac), characterizing the onset of surfactant binding to DNA, does not vary significantly with the architecture of the headgroup. However, comparing with the ...
Effect of Headgroup on DNA−Cationic Surfactant Interactions
Dasgupta, Antara; Das, Prasanta Kumar; Dias, Rita S.; Miguel, Maria G.; Lindman, Björn; Jadhav, Vaibhav M.; Gnanamani, Muthaiah; Maiti, SouvikThe interaction behavior of DNA with different types of hydroxylated cationic surfactants has been studied. Attention was directed to how the introduction of hydroxyl substituents at the headgroup of the cationic surfactants affects the compaction of DNA. The DNA−cationic surfactant interaction was investigated at different charge ratios by several methods like UV melting, ethidium bromide exclusion, and gel el...
Coil−Globule Transition of DNA Molecules Induced by Cationic Surfactants: A Dy...
Dias, Rita S.; Innerlohinger, Josef; Glatter, Otto; Miguel, Maria G.; Lindman, BjörnThe compaction and aggregation of DNA induced by cationic surfactants was studied by dynamic light scattering (DLS). Furthermore, the effect on surfactant-compacted DNA of the addition of nonionic amphiphiles and salt was studied. When using sufficiently low amounts of DNA and cetyltrimethylammonium bromide (CTAB), compacted DNA molecules could be monitored by the appearance of a band characterized by lower hyd...
Electrophoretic properties of complexes between DNA and the cationic surfactant...
Dias, Rita S.; Svingen, Roine; Gustavsson, Bodil; Lindman, Björn; Miguel, Maria G.; Åkerman, BjörnWe use agarose gel electrophoresis to characterize how the monovalent catioinic surfactant cetyltrimethylammonium bromide (CTAB) compacts double-stranded DNA, which is detected as a reduction in electrophoretic DNA velocity. The velocity reaches a plateau at a ratio R = 1.8 of CTAB to DNA-phosphate charges, i.e., above the neutralization point, and the complexes retain a net negative charge at least up to R = 2...
DNA and surfactants in bulk and at interfaces
Dias, Rita S.; Pais, Alberto A. C. C.; Miguel, Maria G.; Lindman, BjörnRecent investigations of the DNA interactions with cationic surfactants and catanionic mixtures are reviewed. Several techniques have been used such as fluorescence microscopy, dynamic light scattering, electron microscopy, and Monte Carlo simulations. ; http://www.sciencedirect.com/science/article/B6TFR-4DTKDBD-5/1/765e1b71aa4231659120beb20507f1a2
DNA Interaction with Catanionic Vesicles
Dias, Rita S.; Lindman, Björn; Miguel, Maria G.DNA−cationic liposome complexes as possible vehicles for gene delivery is currently an important issue. In this work, the interaction between DNA and thermodynamically stable, spontaneously formed, catanionic vesicles with a net positive charge is studied. A phase map was drawn for the aqueous system of DNA and positively charged vesicles, composed of CTAB (cetyltrimethylammonium bromide) and SOS (sodium octyl ...
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