Behaviour of acridine orange in aqueous and in water/ AOT/ decane w/ o microemulsion medium in presence of additives

Abstract

The monomer-dimer equilibrium of the dye acridine orange (AO) has been investigated in the absence and presence of polymer and KCI in decane/ AOT/water microemulsion at nine different compositions with [waterV[AOTj ratios ranging from 5.7-24.7 by spectrophotomeric method. In the concentration range of 10-100 .µmol dm - 3 studied, AO exists mainly in the monomeric form in the microemulsion medium. The dye also does not interact with the polymer, Na salt of carboxymethylcellulose (CMC) in the compartmentalised medium. Variation of water: AOT mole ratio or dye: polymer mole ratio does not affect the spectral pattern. At local KCl concentration of 10 mmol dm - 3 in microemulsion medium (ω = 24.7), the dye self-associates with monomer and dimer formsexisting in equal proportions. At other ω values of 14.8, 9.27 and 5.7, the equilibrium shifts towards monomeric side.