Dielectric study of the double helix to single coil transition of DNA

Author

Georgakilas, A.G. ; Haveles, K.S. ; Sideris, E.G. ; Konsta, A.A.

Author_Institution

Inst. of Biol., Nat. Center for Sci. Res., Athens, Greece

Volume

5

Issue

1

fYear

1998

fDate

2/1/1998 12:00:00 AM

Firstpage

26

Lastpage

32

Abstract

The authors investigated the dielectric behavior of mammalian DNA macromolecules of different sizes in aqueous solution, by dielectric relaxation spectroscopy in the frequency range 100 Hz to 1 MHz, during the double helix to single coil thermal transition, in association with the gradual disruption of the hydrogen bonds between the complementary nitrogenous bases of the DNA double helix, measured by thermal transition spectrophotometry. The authors´ results have shown that, when the temperature of DNA samples is gradually increasing, changes in specific conductivity σ_dc precede changes in A₂₆₀ absorbance at the UV region, where A₂₆₀ is related to the disruption of the hydrogen bonds between the two DNA strands. The presented experimental evidence extends the validation of multistage models for this transition phase to the case of large size mammalian native macromolecular DNA

Keywords

DNA; bioelectric phenomena; biothermics; dielectric relaxation; molecular biophysics; spectrophotometry; 100 Hz to 1 MHz; 260 nm; DNA samples temperature; UV region; hydrogen bonds disruption; large size mammalian native macromolecular DNA; mammalian DNA macromolecules dielectric behaviour; nitrogenous bases; single coil DNA transition; specific conductivity changes; thermal transition spectrophotometry; transition phase; Coils; Conductivity; DNA; Dielectric losses; Dielectric measurements; Electrochemical impedance spectroscopy; Frequency measurement; Hydrogen; Physics; Size measurement;

fLanguage

English

Journal_Title

Dielectrics and Electrical Insulation, IEEE Transactions on

Publisher

ieee

ISSN

1070-9878

Type

jour

DOI

10.1109/94.660755

Filename

660755