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Updated: Jun 9, 2026

Magnetic Tweezers for the Measurement of Twist and Torque
Published on: May 19, 2014
DNA-backbone radio resistivity induced by spin blockade effect
Ramin M Abolfath1, Thomas Brabec
1Department of Radiation Oncology, University of Texas, Southwestern Medical Center, Dallas, Texas 75390, USA. Ramin.Abolfath@utdallas.edu
Abstract:
Coherent control of OH-free radicals interacting with the spin-triplet state of a DNA molecule is investigated. A model Hamiltonian for molecular spin singlet-triplet resonance is developed. We illustrate that the spin-triplet state in DNA molecules can be efficiently populated, as the spin-injection rate can be tuned to be orders of magnitudes greater than the decay rate due to small spin-orbit coupling in organic molecules. Owing to the nano-second life-time of OH free radicals, a non-equilibrium free energy barrier induced by the injected spin triplet state that lasts approximately longer than one-micro second in room temperature can efficiently block the initial Hydrogen abstraction and DNA damage. For a direct demonstration of the spin-blockade effect, a molecular simulation based on an ab-initio Car-Parrinello molecular dynamics is deployed.
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