Low frequency dispersion in the electrophoretic mobility of DNA and mononucleosomes

摘要

The technique of applying a sinusoidal electric field across the sample in the course of a quasielastic light scattering experiment (QELShyphen;SEF) is similar in design to dielectric relaxation methods except the spectral density of the scattered light is monitored instead of the electrical properties of the system. The QELShyphen;SEF technique was employed in a study of T7 DNA and mononucleosomes for driving frequencies of less than 100 Hz. These data suggest a dispersion in the electrophoretic mobility similar to that reported for dielectric relaxation on polynucleotides. These data are interpreted in terms of collective motions of the polyions as mediated by fluctuations in the distribution of small ions.