Abstract
A 7Li and 133Cs NMR relaxation study of macroscopically oriented hydrated Li- and Cs-DNA fibers at three different magnetic fields is presented. Two-dimensional quadrupolarecho and spin-echo techniques were used to determine the homogeneous linewidths free from the broadening due to magnetic field inhomogeneity and to a small distribution of the orientation of DNA helix axes. The relaxation rates obtained show the presence of quadrupolar, dipolar, and paramagnetic relaxation processes in Li-DNA. The separation of these relaxation contributions was made by studying H 2O/ D 2O exchanged samples and (for Li-DNA) 6Li relaxation. For Cs-DNA, the dipolar and paramagnetic contributions are negligible, but relaxation caused by site-exchange modulation of the Cs chemical shift can be observed. The observed relaxation behavior of the two ions is interpreted in terms of two molecular motions on different time scales.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
