Rehydration of CTMA Modified DNA Powders Observed by NMR

Abstract

The rehydration of salmon sperm deoxyribonucleic acid (DNA) and cetyltrimethylammonium chloride (C19H42ClN) complexes was observed using hydration kinetics, sorption isotherm, and high power proton relaxometry (at 30 MHz). The hydration kinetics shows (i) a very tightly bound water not removed by incubation over silica gel (A

Mild hydration of didecyldimethylammonium chloride modified DNA by 1H-nuclear magnetic resonance and by sorption isotherm

“…Previous experiences proved such a time sufficient to arrive at a constant mass. 3 The hydration level was Dm/m 0 ¼ 0.0823 6 0.0017. The observed dehydration followed a single exponential decay with time constant…”

Temperature evolution of hydration shells in solid DNA didecyldimethylammonium chloride complex studied by 1H NMR spectroscopy

“…However, there is still running debate how far DNA condensed with a cationic surfactant retains affinity to water, however significantly weaker. For example, in the case of the most extensively investigated DNA complex with hexadecyltrimetyl ammonium chloride (CTMA), at 80% RH materials' moisture uptake attains about half of the value for native DNA [19,16]. Nevertheless, little is known about the behavior of the complexes at low hydration form.…”

Thermal degradation of biological DNA studied by dielectric spectroscopy

“…In the case of DNA complexes, aliphatic (and so hydrophobic) tails of surfactant molecules extend to outermost directions, making possible to dissolve the complex in some organic solvents [7]. However, even this hydrophobic cocoon does not protect entirely the DNA backbone from water molecules penetrating from the surrounding atmosphere [8][9][10]. Water molecules confined in either DNA or DNA complex belong to a one of two pools, according to the strength and the character of the binding mechanism.…”