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Mesure de la dispersion diélectrique en très basse fréquence de solutions de DNA
Author(s) -
Hanss Maxime
Publication year - 1966
Publication title -
biopolymers
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.556
H-Index - 125
eISSN - 1097-0282
pISSN - 0006-3525
DOI - 10.1002/bip.1966.360040908
Subject(s) - chemistry , conductivity , polarization (electrochemistry) , dispersion (optics) , relaxation (psychology) , electrical resistivity and conductivity , diffusion , low frequency , electrode , biopolymer , range (aeronautics) , analytical chemistry (journal) , thermodynamics , optics , physics , chromatography , polymer , materials science , quantum mechanics , psychology , social psychology , organic chemistry , astronomy , composite material
Based on the four electrodes technique, an apparatus is described which measures the Very Low Frequency (VLF) conductivity of ionic solutions, all electrode effects being completely eliminated. It is thus possible to measure the conductivity frequency dependence between 0.8 and 500 cps, with a relative error of 10 −4 . Applying this method to DNA solutions, one always finds a conductivity dispersion in the VLF range, which disappears when the biopolymer is heat‐denatured. The relaxation time is different from one solution to another, but is always greater than 10 msee. approximately, sometimes even greater than 0.1 sec., the upper limit which one can estimate with our apparatus. The different, explanations of the DNA very low frequency polarization, assuming that its relaxation is connected with the rotational diffusion of the biopolymer long axis, is discussed.