Polyelectrolyte-dye interactions : Study of interaction between Sodium Carboxymethylcellulose and Acridine Orange

The interaction between Sodium Carboxymethylcellulose (NaCMC) and a fluorescent cationic dye, Acridine Orange (AO) has been investigated by spectrophotometric and spectrofluorometric methods. The polymer induces metachromasy in the dye as evidenced from the considerable blue shift in the absorption maximum of the dye. The interaction constant and thermodynamic parameters of polymer-dye interactions have been determined by the absorbance and fluorescence measurements. The effect of additives such as alcohols and urea on the reversal of metachromasy has been studied. The data has been used to determine the stability of the metachromatic complex and the nature of binding.