Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
2817595 | Gene | 2012 | 14 Pages |
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 0.56 eV, 0.33 eV, 0.24 eV, and 0.05 eV 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 300 K which is corresponding to a linear electron density n = 8.66 × 10^3 cm^− 1 at 300 K. 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.
Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (164 K)Download as PowerPoint slideHighlights► A model is presented to explain the role of localized electrons in the bands. ► Delocalization of charges thorough DNA occurs due to its natural movements. ► The localized electrons control the transfer of the positive charges. ► Localized charge-carriers have characteristic relaxation times and charge density. ► Each DNA molecule has four intrinsic thermal activation energies.