Fluorescence polarization changes in electrically oriented solutions of dye-tagged polymers

Dilute aqueous solutions of poly(methacrylic acid) (M = 7.8 × 10⁵) and sodium polystyrene sulphonate (M = 1.3 × 10⁵) when tagged with the dye acridine orange, have been subjected to pulsed electric fields. Changes have been recorded for the polarized components of the fluorescence with each polymer system, during the application of the electric fields. From these fluorescent changes, which were recorded for wavelengths above 515 nm when radiation of 488 nm was incident, the nature of binding of the dye to these polymers has been estimated. For each system, the planar dye molecules appear to bind parallel to the polymer backbone.