Three-Dimensional Fluorescence Spectral Analysis on the Binding Interaction of Alizarin Red Dye in Reverse Micelle

Abstract

 In this work, we have focused on the photophysical properties of Alizarin red dye (Sodium salt of 1,2-dihydroxy-9,10-anthraquinone-3-sulfonic acid)  in reverse micelle, particularly anionic micelle, AOT. Binding interactions of Alizarin Red Dye in AOT reverse micelles are analyzed using two dimensional (2D) (steady state) fluorescence and three dimensional (3D) fluorescence spectroscopy. On increasing the size of water pool (W₀ from 0 to 60), there was considerable enhancement in the absorption as well as fluorescence intensity with red shift indicated that the alizarin red dyes confined in the core of the reverse micelles and has a strong interaction with the sulfonate head group.  Fluorescence technique was used. The binding parameters (binding sites, ~ 1 (0.94) and binding constant, 3.395 C 10⁴ M^-1), quantum yield (0.074), partition coefficient (6.5 C 10⁴), excited state pKa value (6) are determined with the aid of fluorescence technique. The observed results suggest that the fluorescence spectral analysis can be successfully used to study the binding interaction of any type of dyes in microheterogeneous media.