Fluorescence Spectroscopy Study on the Interaction of Acetal Cleavable Anionic Surfactants and Bovine Serum Albumin

Abstract

The interactions between bovine serum albumin (BSA) and two cleavable anionic surfactants, sodium 3-[(2-nonyl-1,3-dioxolan-4-yl)methoxy]propane-1-sulfonate (SNPS) and sodium 3,3′-(2-nonyl-1,3-dioxane-5,5-diyl)bis(methylene)bis(oxy)dipropane-1-sulfonate (SNDPS), have been studied by means of fluorescence spectroscopy and thermodynamic analysis. The fluorescence of BSA is quenched via a static quenching mechanism with the addition of the surfactants. The binding constants of the surfactants and proteins have been measured, with KA(SNPS) = 8.71×104 M−1 and KA(SNDPS) = 7.08 × 104 M−1, respectively. The interaction between surfactants and BSA is mainly of hydrophobic nature, based on the number of binding sites, n[n(SNPS) = 1.57, n(SNDPS) = 1.47], and the thermodynamic relationship. These results suggest that SNPS and SNDPS could be effective protein denaturants for protein separation and analysis.