DNA helixes have been established as model systems for analyzing electron spin-spin coupling due to the stability and well-known structures of DNA.  Studies initially pursued magnetic coupling interactions between a nitroxide radical covalently linked to one DNA strand and a lanthanide metal covalently linked to its complement (Biczo and Hirsh, 2009).  However, the length and flexibility of the 3-carbon linker attaching the radical to the 5'-phosphate of the DNA strand causes the location of the spin label to be ambiguous.  We describe the preparation and characterization of DNA strands with a shorter covalent linkage to the nitroxide spin-label. The spin-label is attached to the 3'-terminus of the DNA strand via the 2' carbon of deoxyribose. These new duplexes were found to also have B-form structure, lower melting temperature, and comparable molar enthalpies to duplexes containing 3-carbon linked radicals. Duplex properties were characterized using EPR, UV-Vis and CD spectrometry.

Thermodynamic characterization of DNA duplexes with direct nitroxide radical attachment to ribose rings

243rd National Meeting (2012)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.