Embedding DNA in surfactant mesophases: The phase diagram of the ternary system dodecyltrimethylammonium-DNA/monoolein/water in comparison to the DNA-free analogue.

摘要: The self-assembly of a true ternary mixture comprising an electroneutral complex DNA anions and surfactant cations (dodecyltrimethylammonium cations, DTA), water, nonionic (monoolein, MO) has been studied. phase diagrams two systems, DTA-DNA/MO/water and, for comparison, dodecyltrimethylammonium bromide (DTAB)/MO/water, were obtained by visual inspection, microscopic examination under polarized light, small-angle X-ray scattering (SAXS) deuterium NMR ((2)H NMR) at 298K normal pressure. isothermal diagram the system contains four liquid crystalline (LC) regions (reversed hexagonal, Pn3m, Ia3d, lamellar). supramolecular assemblies evolve from bicontinuous cubic structure reversed type to two-dimensional hexagonal as content DTA-DNA is increased. While tends form phase, DTAB incorporated into existing lamellar formed MO water giving rise swelling significant extension region. There only small tendency phases in binary MO/water accommodate or DTA-DNA. (Less)