title: Concepts on charge transfer through naturally vibrating DNA molecule.
abstract: Delocalization of charges thorough DNA occurs due to the natural and continuous movements of molecule which stimulates the charge transfer through the molecule. A model is presented showing that the mechanism of electrical conduction occurs mainly by thermally-activated drift motion of holes under control of the localized carriers; where electrons are localized in the conduction band. These localized (stationary-trapped) electrons control the movements of the positive charges and do not play an effective role in the electrical conduction itself. It is found that the localized charge-carriers in the bands have characteristic relaxation times at 5×10(^-2)s, 1.94×10(^-4)s, 5×10(^-7)s, and 2×10(^-11)s respectively which are corresponding to four intrinsic thermal activation energies 0.56eV, 0.33eV, 0.24eV, and 0.05eV respectively. The ac-conductivity of some published data are well fitted with the presented model and the total charge density in DNA molecule is calculated to be n=1.88×10(^19)cm(^-3) at 300K which is corresponding to a linear electron density n=8.66×10(^3)cm(^-1) at 300K. The model shed light on the role of transfer and/or localization of charges through DNA which has multiple applications in medical, nano-technical, bio-sensing and different domains. So, repair DNA by adjusting the charge transport through the molecule is future challenges to new medical applications.
authors.affiliation: Physics Department, Faculty of Science, King Abdulaziz University at Jeddah, Saudi Arabia. smabdullah@kau.edu.sa
authors.forename: S
authors.initials: S
authors.lastname: Abdalla
authors.forename: F
authors.initials: F
authors.lastname: Marzouki
mesh_terms: D055592:Biophysical Phenomena; D004247:DNA / Q000737:chemistry* / Q000378:metabolism*; D004249:DNA Damage; D004553:Electric Conductivity; D004579:Electron Transport; D004583:Electrons; D008954:Models, Biological; D037742:Nanotubes, Carbon / Q000737:chemistry; D055672:Static Electricity; D013816:Thermodynamics; D014732:Vibration
chemical_list: D037742:Nanotubes, Carbon; D004247:DNA