Linear Dichroic Spectra of Dna-Crystal Violet Complexes Under Flow Fields

Abstract

The linear dichroic spectra of DNA-Crystal Violet complexes under flow were measured in the visible absorption region of Crystal Violet at three mixing ratios. The reduced dichroism was both positive (>620 nm) and negative (620–400 nm). The average angles between the transition moments and the orientation axis were estimated.

Pulsed Electric Linear Dichroism of Triphenylmethane Dyes Adsorbed on Montmorillonite K10 in Aqueous Media

“…Figure 3 shows the isotropic absorption spectra of CV in the absence (dotted line) and the presence (solid and dashed lines) of MK-10 at two D/S values in (c), and the corresponding reduced dichroism spectra at 3 kV/cm in (a) and (b). These absorption spectra are very close to those previously reported for CV-clay solutions (38,39) and for many CV-polyelectrolyte complexes, such as polyphosphates (24,26), DNA (25), and poly(α,L-glutamic acid) (27), to name a few. The broadening of the spectrum and the appearance of the so-called metachromatic bands in the presence of MK-10 ( Fig.…”

“…For the present purpose, the ELD spectra of two monocationic triphenylmethane dyes, crystal violet (hereafter abbreviated as CV) and malachite green (hereafter abbreviated as MG), were measured in the presence of MK-10 under conditions closely related to the electric birefringence measurements of MK-10 itself (19,20). These two highly symmetric dyes have been studied extensively for their interaction with a number of biopolymers and related polyelectrolytes (24)(25)(26)(27)(28). Fortunately, the transition dipole moments of these dyes, embedded in poly(vinyl alcohol) films, have been determined by the stretched film dichroism method, the results showing that each dye possesses an out-of-plane transition overlapping with intense inplane transitions in the visible wavelength region (29,30).…”